Read the following passage and questions, then choose the right answer from options, the answer should be one of A, B, C, D.

<passage>:
Mac Albin pushed the little red switch from him. Max Alben pulled the little red switch toward him. the trick is Mac Albin pushed the little red switch from him. It was a good job and Max Alben knew whom he had to thank for it—his great-grandfather. "Good old Giovanni Albeni," he muttered as he hurried into the laboratory slightly ahead of the escorting technicians, all of them, to do it before you have a chance to undo it! ... pulled the little red switch toward him. ... pushed the little red switch from him. He shrugged rapidly out of his rags, as he had been instructed in the anteroom, and stepped into the housing of the enormous mechanism. This was the first time he had seen it, since he had been taught how to operate it on a dummy model, and now he stared at the great This machine, the pride and the hope of 2089, was something almost outside his powers of comprehension. But Max Alben knew how to run it, and he knew, roughly, what it was supposed to accomplish. He knew also being scientifically unpredictable, might well be the death of him. "Good old Giovanni Albeni," he muttered again affectionately. If his great-grandfather had not volunteered for the earliest time-travel experiments way back in the nineteen-seventies, back even before the Blight, it would never have been discovered that he and his He would still be patrolling the barbed wire that surrounded the three livestock wealth of the Western Hemisphere—thoroughly content with the half-pail of dried apricots he received each and every payday. No, if his great-grandfather had not demonstrated long ago his unique capacity for remaining conscious during time travel, Max Alben would not now be shifting from foot to foot in a physics laboratory, Men like O'Hara, who controlled mushrooms, Levney, the blackberry the far side of the room and was approaching him with a sealed metal cylinder in one hand. "We've decided to add a further precaution at the last moment," the old man said. "That is, the scientists have suggested it and I have—er—I isn't it?" he asked, suddenly uncertain. "Yes, sir," one of the technicians standing by the time machine said "Ah, yes, the red switch. He pulls the little red switch toward him. red switch on the green instrument panel toward him, thus preventing Alben kept his eyes deferentially in their direction, too, as he had He knew who ruled his world—these stolid, well-fed men in clean where Alben stood in the entrance of the time machine and handed the sealed metal cylinder to him. "This is the precaution the scientists Max Alben gulped and nodded violently. He darted to the rear of the machine and turned the dial which activated it. flick! It was a good job and Mac Albin knew whom he had to thank for it—his great-grandfather. "Good old Giovanni Albeni," he laughed as he looked at the morose faces of his two colleagues. Bob Skeat and Hugo Honek had done as much as he to build the tiny time machine in the secret lab under the helicopter garage, and they were fully as eager to go, but—unfortunately for them—they were not descended from the right ancestor. Leisurely, he unzipped the richly embroidered garment that, as the father of two children, he was privileged to wear, and wriggled into the housing of the complex little mechanism. This was hardly the first time he had seen it, since he'd been helping to build the device from the moment Honek had nodded and risen from the drafting board, being put into operation. But it meant a lot more to Mac Albin than death. "Good old Giovanni Albeni," he laughed again happily. If his great-grandfather had not volunteered for the earliest time-travel experiments way back in the nineteen-seventies, back even before the Epidemic, it would never have been discovered that he and And if that had not been discovered, the Albins would not have become life-guarding world the Earth had become, Mac Albin would never have been reluctantly selected by his two co-workers as the one to carry the forbidden banner of dangerous experiment. No, if his great-grandfather had not demonstrated long ago his unique capacity for remaining conscious during time travel, Mac Albin would Albin and Honek watched him stuff several sheets of paper into a small metal box which he closed without locking. "Oh, it won't be that bad," Albin reassured him absent-mindedly from "But Bob and you both tried to operate the machine," Albin reminded Albin. "The Security Council is just trying to solve the problem in Albin turned it around curiously. "How?" Albin laughed. "That's just looking for trouble." "What do I do with it—hand it to the guy from the alternate 2089?" The small fat man exasperatedly hit the side of the time machine with Albin grimaced in annoyance. "I "That I'll promise you," Albin said a trifle disgustedly. "It'll end He twisted around, reaching overhead for the lever which activated the forces that drove the time machine. flick! It was strange, Max Alben reflected, that this time travel business, which knocked unconscious everyone who tried it, only made him feel slightly dizzy. That was because he was descended from Giovanni Albeni, he had been told. There must be some complicated scientific explanation for it, he decided—and that would make it none of his business. Better All around the time machine, there was a heavy gray murk in which Carefully, carefully, like a man handling a strange bomb made on a pull the red switch toward him. Then his well-paid assignment would be He stopped and scratched his dirt-matted hair. Wasn't there something he was supposed to do a second before materialization? Yes, that useless old windbag, Sadha, had given him a last instruction. He picked up the sealed metal cylinder, walked to the entrance of the time machine and tossed it into the gray murk. A solid object floating he opened it, hoping to find something valuable. Nothing but a few mumps virus that several of the men in the fleet were incubating at the Max Alben finished the manuscript and sighed. What a wonderful world! It was odd, Mac Albin reflected, that these temporal journeys, which induced coma in everyone who tried it, only made him feel slightly dizzy. That was because he was descended from Giovanni Albeni, he knew. Maybe there was some genetic relationship with his above-average fertility—might be a good idea to mention the idea to a biologist or All around the time machine, there was a soupy gray murk in which butler had not been told to turn on the ground lights. surgical robots at an unusually difficult birth, he watched the exactly crucial moment. Then he pushed a button and froze the machine push the red switch from him. Then his exciting adventure would be over. He paused and tapped at his sleek chin. He was supposed to do something He picked up the small metal box, twisted around to face the opening of the time machine and dropped it into the gray murk. A solid object A sealed metal cylinder. Strange. What was it doing out there? Anxiously, he opened it, not daring to believe he'd find a document inside. Yes, that was exactly what it was, he saw excitedly. He began Mac Albin finished the document and sighed. What a magnificent world! He dropped his hand on the side levers and began the process of even the black market kings, had all warned him not to go ahead with He materialized the time machine around the green instrument panel, Max Alben pulled the little red switch toward him. reality all around him, Mac Albin felt a bit of shame at what he was doing. He'd promised Bob and Hugo to drop the experiment at any stage of his unused muscles. He was tired of having to undertake a simple carry on the race, went to the wall? His kind wouldn't. duped by the technicians into permitting the experiment how he felt: his world was drowsily moribund Albin decided that he was experiencing renunciation and felt proud. He materialized the time machine around the green instrument panel,

<question>:
What had Albin had to do with the machine before he got inside it?

<options>:
A He had helped build it
B He had never seen it before
C He had seen it once before
D His great grandfather had helped build it

<answer>:

A