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

<passage>:
like him. But it's a longish story, and you might as well let me in. You will, you know, so why quibble about it? At least, you always don't have the right attitude toward tenses for a situation like this. Anyhow, you'll let me in. I did, so you will. Thanks. You think you're crazy, of course, but you'll find out you aren't. It's just that things are a bit confused. And don't look at the machine out there too long—until you get used to it, you'll find it's You're wondering whether to give me a drink, as I remember it. Why not? And naturally, since we have the same tastes, you can make the same for I felt the same way when he—that is, of course, I or we—came back to tell me about it, thirty years ago. Here, have one of these. You'll get to like them in a couple more sense things. So I'll simply go ahead talking for half an hour or so, until you get over it. After that you'll come along with me. You know, I could try to change things around by telling but he—I—told me what I was going to do, so I might as well do the same. I probably couldn't help telling you the same thing in the same words, even if I tried—and I don't intend to you'll want to go along. I'll be tired of talking by then, and in a hurry to get going. So I isn't protected, though. that. Well, I asked it after I was told, then I came back and told it to you, and I still can't help answering when you speak. "Not exactly," I try to explain. "Maybe it's no dimension—or it might be the fifth of simple, short-limbed, one-piece affair I put on, but it feels comfortable. "I'm staying here," I tell you. "This is like the things they wear in this century, as near as I can remember it, and I should be able to pass fairly well. I've had all my fortune—the one you make on that atomic generator—invested in such a way I can get it on using some identification I've got with me, so I'll do all right. I know they still use some kind of money, you'll see evidence of that. And it's a I'll leave you. I like the looks of things here, so I won't be coming back with you." anyway?" I'd told you that, too, but you've forgotten. "As near as I can guess, you see me going by, mixed into a crowd that is loafing along toward a restaurant, or something like it, that is just opening. I'm asking questions of a man, who points, and I turn and move off. the hang of the spelling they use, though. Now there are people around you, but nobody pays much attention to you. you, you hear some pretty normal English, but there are others using stuff as garbled as his. The educated and uneducated? I don't know. You go right until you find a big sign built into the rubbery surface 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. of drawl, with softer vowels and slurred consonants, but it's rather pleasant. "Help you, sir? Oh, of course. You must be playing in 'Atoms and whatever you need for realism in your role. Nice show. I saw it twice." "Thanks," you mutter, wondering what kind of civilization can produce guards as polite as that. "I—I'm told I should investigate your display of atomic generators." them to check his latest theory of how they work. Too bad he could not explain the principle, either. Someone will, some day, though. Lord, the genius of that twentieth century inventor! It's quite a hobby with me, sir. I've read everything I could get on the period. 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 of what seem to be bearings, and slips something the size of a penny toward you. "Souvenir," it announces in a well-modulated voice. "This is a typical gem of the twentieth century, properly cut to 58 facets, known morning hours for one-tenth credit. If you have more than one child, press the red button for the number of stones you desire." , filled with everything from a crossbow to a tiny rod four inches long and half the thickness of a pencil, marked . By that time, you're almost convinced. And you've been doing a lot of , is about the size of a desk telephone. The earlier ones are larger, of course, clumsier, that this is the first invention which leaped full blown into basically final form. You study it, but it mentions casually the inventor, without giving his name. Either they don't know it, or they take it for granted that everyone does, which seems more probable. They call attention to the built, complete with design drawings, original manuscript on operation, and full patent application. and any amperage up to one thousand, its maximum power output being fifty kilowatts, limited by the current-carrying capacity of the outputs. They also mention that the operating principle is still being investigated, and that only such refinements as better alloys and the addition of magnetric and nucleatric current outlets have been added 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 as the great inventor made it. And it still operates as well as ever. 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 arriving, but I'll be back in about ten minutes. He wants to examine some of the weapons for a monograph on Centaurian primitives compared to nineteenth century man. You'll pardon me?" 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 haven't told you, but a working model such as that is a handy thing. it only weighs about fifty pounds! Naturally, it can be carried. lot of what I say from now on, and have to find out for yourself. But maybe some of it helps. I've tried to remember how much I remembered, 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. an appearance schedule. But you should have come to me." He reaches out and taps a pedestrian lightly on the shoulder. "Sir, an emergency request. Would you help this gentleman?" You did notice the name of the building from which you came and you mutter it. The stranger nods again, reaches out and picks up the other at you both. That way, it isn't so bad. And you begin to see why I decided I might like to stay in the future. But all the same, the organized cooperation here doesn't look too good. The guard can get the same and be there 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 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 It isn't hard to disassemble, but you don't learn a thing just some the makeshift job you've just done. But you begin getting more of a jolt when you find that the papers are letter. But you're thinking of the puzzle. You can't find any answer. One day you come across an old poem—something about some folks

<question>:
Which word doesn't describe the security guard?

<options>:
A knowledgeable
B friendly
C curious
D helpful

<answer>:

C