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

<passage>:
things. So I'll simply go ahead talking for half an hour or so, until you get over it. After that you'll come you'll want to go along. I'll be tired of talking by then, and in a hurry to get going. So I cut off your questions, and get you inside. I snap on a green button, isn't protected, though. You start to say something, but by then I'm pressing a black button, and everything outside will disappear. You look for your house, but turns over and pokes back at you. Doesn't hurt, and when you pull your arm back, you're still sound and uninjured. But it looks frightening and you don't try it again. the machine and I don't understand it." "But...." I let it go, and so do you. If you don't, it's a good way of going apparently, though there is a time effect back in the luggage space. You look at your watch and it's still running. That means you either easier, though we're in complete darkness, except for the weak light in the machine, which always burns, and a few feet of rough dirty cement floor around. You take another cigaret from me and you get out of the machine, just as I do. This is a sub-sub-sub-basement. We have to walk up a flight of stairs, and there is an elevator waiting, fortunately with the door open. "What about the time machine?" you ask. "Since nobody ever stole it, it's safe." We get in the elevator, and I say "first" to it. It gives out a coughing noise and the basement openings begin to click by us. There's grab the motor, and get out. And good luck to you." You act as if you're dreaming, though you can't believe it's a dream. You nod at me and I move out into the main corridor. A second later, You go up the steps, but you see that it seems to be closed. You hesitate for a moment, then. You're beginning to think the whole affair is complete nonsense, and you should get back to the time machine and go home. But then a guard comes to the gate. Except for the short legs in his suit and the friendly grin on his face, he looks like any other guard. display of atomic generators." He beams at that. "Of course." The gate is swung to behind you, but obviously he isn't locking it. In fact, there doesn't seem to be a Oh—congratulations on your pronunciation. Sounds just like some of our oldest tapes." You get away from him, finally, after some polite thanks. The building seems deserted and you wander up the stairs. There's a room on your right filled with something that proclaims itself the first truly press the red button for the number of stones you desire." You put it in your pocket, gulping a little, and get back to the . Apparently that's the way it's fueled. It's about one foot on each side. "Nice," the guard says over your shoulder. "It finally wore out one of the cathogrids and we had to replace that, but otherwise it's exactly Like to have me tell you about it?" "Not particularly," you begin, and then realize bad manners might be conspicuous here. While you're searching for an answer, the guard pulls something out of his pocket and stares at it. "Fine, fine. The mayor of Altasecarba—Centaurian, you know—is arriving, but I'll be back in about ten minutes. He wants to examine thing is absolutely fixed. You can't see any bolts, but you can't budge it, either. You work down the line. It'd be foolish to take the early model if you And, finally, you're right back beside the original first model. It's probably bolted down, too, but you try it tentatively and you find it moves. There's a little sign under it, indicating you shouldn't touch it, since the gravostatic plate is being renewed. Well, you won't be able to change the time cycle by doing anything I it only weighs about fifty pounds! Naturally, it can be carried. You expect a warning bell, but nothing happens. As a matter of fact, after he told me, but I can't be sure. So I'll keep on talking. I probably can't help it, anyhow. Pre-set, you might say. Well, you stagger down the corridor, looking out for the guard, but all You stumble down the stairs, feeling all the futuristic rays in the world on your back, and still nothing happens. Ahead of you, the gate is closed. You reach it and it opens obligingly by itself. You breathe a quick sigh of relief and start out onto the street. Then there's a yell behind you. You don't wait. You put one leg in of your feet, with a sudden ringing sound. You don't wait to find out about that, either. Somebody reaches out a hand to catch you and you catches your arm and you know you're not going to get away, so you stop. "You can't exert yourself that hard in this heat, fellow," the cop says. "There are laws against that, without a yellow sticker. Here, let your head and come up for air. "I—I left my money home," you begin. The cop nods. "Oh, that explains it. Fine, I won't have to give you an appearance schedule. But you should have come to me." He reaches here doesn't look too good. The guard can get the same and be there before you. And he is. He stands just inside the door of the building as you reach it. The stranger lifts an eyebrow and goes off at once when you nod at him, not waiting for thanks. And the guard comes up, holding some dinkus in his hand, about the size of a big folding camera and not too dissimilar in other ways. He snaps it open and you get set to duck. "You forgot the prints, monograph, and patent applications," he says. "They go with the generator—we don't like to have them separated. A this building. Just let us know when you're finished with the model and we'll pick it up." You swallow several sets of tonsils you had removed years before, and take the bundle of papers he hands you out of the little case. He pumps you for some more information, which you give him at random. It seems to satisfy your amiable guard friend. He finally smiles in satisfaction and heads back to the museum. You still don't believe it, but you pick up the atomic generator and the information sheets, and you head down toward the service elevator. Then there's a sort of cough and something dilates in the wall. It forms a perfect door and the elevator stands there waiting. You get in, it's the weak light in the time machine. You've located it. You put the atomic generator in the luggage space, throw the papers down beside it, and climb into the cockpit, sweating and mumbling. You doped out the fact that they'd been robbed, or whether they were trying to help you. You don't care which it is. The field springs up around you and the next button you touch—the one on the board that hasn't nerves settle back to normal. You notice a third set of buttons, with some pencil marks over them—"Press these to return to yourself 30 years"—and you begin waiting for the air to get stale. It doesn't because there is only one of you this time. land in your back yard, and then hop back thirty years to pick up yourself, landing in front of your house. Just that. But right then, you don't care. You jump out and start pulling out that atomic generator and taking it inside. It isn't hard to disassemble, but you don't learn a thing just some in time, somehow, and is back to its original youth—minus the replaced wires the guard mentioned—which probably wore out because of the makeshift job you've just done. put in the museum with you as the inventor so you can steal it to be the inventor. And you do it in a time machine which you bring back to

<question>:
Which isn't something the guard did?

<options>:
A help him carry the atomic generator to the time machine
B help him find the atomic generator
C hand him the patent and other helpful information
D give him time to take it out of the building

<answer>:

A