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

<passage>:
thus it isn't always so! No, you're wrong. I'm not your father's ghost, even if I do look a bit obvious it must be a time machine. You'll sense that, too. You've seen a few buttons on a dash. You'll be puzzling over what I'll tell you, foggy nothing surrounding the cockpit it is probably the field that prevents passage through time from affecting us. The luggage section isn't protected, though. You start to say something, but by then I'm pressing a black button, You can't feel any motion, of course. You try to reach a hand out Then it comes to you slowly that you're actually traveling in time. 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 then the time-machine. And when you closed the loop by going back and saving yourself the trouble, it got all tangled up. I figured out once that such a universe would need some seven or eight time and space dimensions. It's simpler just to figure that this is the way time got bent back on itself. Maybe there is no machine, and it's just easier 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 increment of time from the main field. I don't know, and you won't open, yet you haven't seen any effects of air loss. "Where are we getting our air?" you ask. "Or why don't we lose it?" time nor space, apparently. How could the air leak out? You still feel gravity, but I can't explain that, either. Maybe the machine has a gravity field built in, or maybe the time that makes your watch run is responsible for gravity. In spite of Einstein, you have always had the idea that time is an effect of gravity, and I sort of agree, still. Then the machine stops—at least, the field around us cuts off. You feel a dankish sort of air replace the stale air, and you breathe interstellar civilization." You take another cigaret from me, and follow me. I've got a small flashlight and we grope through a pile of rubbish, out into a corridor. 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. 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 no feeling of acceleration—some kind of false gravity they use in the future. Then the door opens, and the elevator says "first" back at us. It's obviously a service elevator and we're in a dim corridor, with You nod at me and I move out into the main corridor. A second later, You come out of the side corridor and go down a hall, away from the Trav:l Biwrou—F:rst-Clas Twrz—Marz, Viin*s, and x: Trouj:n Planets. Spej:l reits tu aol s*nz wixin 60 lyt iirz! But there is only a single picture of a dull-looking metal sphere, with passengers moving up a ramp, and the office is closed. You begin to get . There's an arrow pointing and you turn lower than they used to, apparently. Twenty floors up seems about the You go up the steps, but you see that it seems to be closed. You go home. But then a guard comes to the gate. Except for the short legs Axioms.' The museum's closed, but I'll be glad to let you study 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 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 lock. "Must be a new part. You go down that corridor, up one flight 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 goes through a crazy wiggle inside, stops turning out a continual row corridor. You turn left and go past a big room in which models of spaceships—from the original thing that looks like a V-2, and is labeled first Lunar rocket, to a ten-foot globe, complete with miniature manikins—are sailing about in some kind of orbits. Then . Beyond is the end of the corridor, and a big conspicuous here. While you're searching for an answer, the guard pulls thing is absolutely fixed. You can't see any bolts, but you can't budge some other principle?—and nuclear binding-force energy terminals. But they're all held down by the same whatchamaycallem effect. 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. You expect a warning bell, but nothing happens. As a matter of fact, 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 There's another yell behind you. of your feet, with a sudden ringing sound. You don't wait to find out heavier at every step. Reaction sets in a bit and your knees begin to buckle, but you shake out and taps a pedestrian lightly on the shoulder. "Sir, an emergency Pedestrians begin to move aside, and you and the stranger jog down the the information sheets, and you head down toward the service elevator. There is no button on it. In fact, there's no door there. You start looking for other doors or corridors, but you know this is right. The signs along the halls are the same as they were. forms a perfect door and the elevator stands there waiting. You get in, the deuce would that lowest basement be called? But the elevator has closed and is moving downward in a hurry. It coughs again and you're at the original level. You get out—and realize you don't have a light. in the direction of the time machine, bumping against boxes, staggering here and there, and trying to find the right place by sheer feel. Then a shred of dim light appears it's the weak light in the time machine. down beside it, and climb into the cockpit, sweating and mumbling. You reach forward toward the green button and hesitate. There's a red one Suddenly, there's a confused yell from the direction of the elevator it. Your finger touches the red button. you and the next button you touch—the one on the board that hasn't been used so far—sends you off into nothingness. There is no beam of nerves settle back to normal. You notice a third set of buttons, with because there is only one of you this time. Instead, everything flashes off and you're sitting in the machine in machine in front of your house, go to the future in the sub-basement, And with the controls set at 120 volts, 60 cycles and 15 amperes, you feel a little happier when you realize that the luggage space wasn't insulated from time effects by a field, so the motor has moved backward in time, somehow, and is back to its original youth—minus the calling it evolution and others calling it God. You go out, make a few provisions for the future, and come back to climb into the time machine that's waiting in the building you had put around it. Then you'll be

<question>:
Why is there no feeling of acceleration in the elevator in the future?

<options>:
A The force is too fast to be felt.
B The elevator doesn't actually move, only the scenery does.
C It's moving slower in opposition to the gravity.
D The false gravity used in the interstellar civilization.

<answer>:

D