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

<passage>:
This was Burnett's last trip. Three more He heard the star-port grind open, and the movement of the metal claws Constellation . Opening the star-port. Extending the retriever claw. Plucking some poor full-cargoed with a lot of warriors who didn't laugh or talk or smoke, who just lay on their shelves, all one hundred of them, waiting for a decent burial. "Number ninety-eight." Coming matter of fact and slow, Rice's voice from the ceiling radio hit Burnett. "Number ninety-eight," Burnett repeated. "Working on ninety-five, ninety-six and ninety-seven now. Blood-pumps, preservative, slight surgery." Off a million miles away his voice was talking. It sounded deep. It didn't belong to him anymore. Rice said: "Boyohbody! Two more pick-ups and back to New York. Me for a ten-day drunk!" Burnett peeled the gloves off his huge, red, soft hands, slapped them another in galactic fury, to sidle up behind gutted wrecks of ships, salvaging any bodies still intact after the conflict. Two men. Rice and himself. Sharing a cozy morgue ship with a hundred other men who had forgotten, quite suddenly, however, to talk again. Ten years of it. Every hour of those ten years eating like maggots life, even while preservative was being pumped into their veins. "Sam! On the double! Up the rungs!" Burnett closed his eyes and said a couple of words, firmly. Nothing was worth running for any more. Another body. There had been one hundred thousand bodies preceding it. Nothing unusual about a body with blood cooling in it. without making any noise on the rungs. He kept thinking the one thing he couldn't forget. feet forever and forever with no goal. Bits of flesh in ruptured space suits, mouths open for air that had never been there in a hundred extended the retriever-claw and culled them into the air-lock. and who the next ones would be. After ten years you made yourself blind to them. You went around doing his experienced glance knew that. He didn't know what it was. too dead. Rice exploded. His eyes were hot in his young, sharp-cut face, hot and black. "Good Lord, Sam, do you know who this is?" Burnett scowled uneasily and said no. "It's Lethla!" Rice retorted. Burnett said, "Lethla?" And then: "Oh, yes! Kriere's majordomo. That Sam opened his thin lips and the words fell out all by themselves. "Look, Rice, you're new at this game. I've been at it ever since the battle-cuiser to go against him?" "We'll radio for help?" "Yeah? If there's a warship within our radio range, seven hundred thousand miles, we'll get it. Unfortunately, the tide of battle has swept out past Earth in a new war concerning Io. That's out, Rice." Rice stood about three inches below Sam Burnett's six-foot-one. Jaw bloated and crushed by space pressures and heat-blasts. Fine lads who start out smiling and get the smile burned off down to the bone—" care much how I go back to earth. This Venusian here—what's his name? Lethla. He's number ninety-eight. Shove me into shelf ninety-nine beside him and get the hell home. That's how I feel!" Rice was going to say something, but he didn't have time. He rose from the floor with slow, easy movements, almost like a dream. He didn't say anything. The heat-blast in his white fingers did all the inserted, hidden in the uniform, ending in thin globules of oxygen. He spoke. Triumph warmed his crystal-thin voice. "That's how I did it, Lethla nodded. His milk-blue eyes dilated. "Very marvelously pared to an unbreakable thickness of one-thirtieth of an inch worn only on the head. You have to look quickly to notice it, and, unfortunately, viewed at all." Prickles of sweat appeared on Rice's face. He swore at the Venusian and metal and glass and coils. The radio. He smiled. "That's better. Now. We can talk—" Rice said it, slow: "Interplanetary law declares it straight, Lethla! Get out! Only dead picked up— now! " Rice didn't move. Burnett moved first, feeling alive for the first time board the Constellation On the way up, Burnett thought about it. About Lethla poised like a white feather at the top, holding death in his hand. You never knew whose body would come in through the star-port next. Number ninety-eight was Lethla. Number ninety-nine would be Kriere. There were two shelves numbered and empty. They should be filled. And what more proper than that Kriere and Lethla should fill them? But, he chewed his lip, that would need a bit of doing. And even then the cargo wouldn't be full. Still one more body to get one hundred. And you never knew who it would be. He came out of the quick thoughts when he looped his long leg over Burnett set his teeth together, bone against bone. Help Kriere escape? Two muscles moved on Burnett, one in each long cheek. The sag in his Burnett laughed through his nose. Controls moved under his fingers like "We're about fifty miles from him, catching up." Burnett turned to Lethla with an intent scowl. Funny. This was the first and the last time anybody would ever board the There was a way. And there was a weapon. And the war would be over and this would be the last trip. was too much silence, and his voice sounded guilty standing up alone in the center of that silence. "Take controls, Rice. I'll manipulate the star-port." was about to end a ten-years' war. There was only one way of drawing Lethla off guard, and it had to be fast. Burnett jabbed a purple-topped stud. The star-port clashed open as it had done a thousand times before but for the first time it was a good sound. And out of the star-port, at Sam Burnett's easily fingered directions, slid the long claw-like mechanism that picked up bodies He watched while Burnett exhaled, touched another lever and said: "You know, Lethla, there's an old saying that only dead men come aboard the Constellation . I believe it." And the claw closed as Burnett spoke, closed slowly and certainly, all Burnett spun about and leaped. The horror on Lethla's face didn't go away as he fired his gun. Rice came in fighting, too, but not before something like a red-hot claws come inside, and the star-port grind shut. "Maybe. I dunno. Kind of nice to think of all those kids who'll never have to come aboard the Constellation , though, Rice." His voice trailed off. "You watch the shelves fill up and you never know who'll be next. Who'd have thought, four days ago—" Something happened to his tongue so it felt like hard ice blocking his mouth. He had a lot more words to say, but only time to get a few of them out: "Rice?" "Yeah, Sam?" "Full enough for me, sir." "But still not full. If we went back to Center Base without filling the shelves, it wouldn't be right. Look there—number ninety-eight is Lethla—number ninety-nine is Kriere. Three thousand days of rolling this rocket, and not once come back without a bunch of the kids who want to sleep easy on the good green earth. Not right to be going back million miles. "Ain't I one hell of a patriot, Rice?" dissolve. Ninety-eight: Lethla. Ninety-nine: Kriere. He could still see Rice standing over him for a long time, breathing And then he said softly: " One hundred. "

<question>:
How many times did Burnett operate the claw in the passage?

<options>:
A Three
B Two
C Four
D One

<answer>:

D