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

<passage>:
The gadget was strictly, beyond any question, a toy. Not a real, workable device. Except for the way it could work under a man's mental skin.... BY HARRY HARRISON Because there were few adults in the crowd, and Colonel "Biff" Hawton stood over six feet tall, he could see every detail of the demonstration. The children—and most of the parents—gaped in wide-eyed wonder. Biff Hawton was too sophisticated to be awed. He stayed on because he wanted to find out what the trick was that made the gadget work. said, holding up a garishly printed booklet opened to a four-color diagram. "You all know how magnets pick up things and I bet you even know that the earth itself is one great big magnet—that's why compasses always point north. Well ... the Atomic Wonder Space Wave Tapper hangs onto those space waves. Invisibly all about us, and even going right through us, are the magnetic waves of the earth. The Atomic Wonder rides these waves just the way a ship rides the waves in the ocean. Now watch...." Every eye was on him as he put the gaudy model rocketship on top of the table and stepped back. It was made of stamped metal and seemed as incapable of flying as a can of ham—which it very much resembled. Neither wings, propellors, nor jets broke through the painted surface. It rested on three rubber wheels and coming out through the bottom was a double strand of thin insulated wire. This black table and terminated in a control box in the demonstrator's hand. An indicator light, a switch and a knob appeared to be the only controls. "I turn on the Power Switch, sending a surge of current to the Wave Receptors," he said. The switch clicked and the light blinked on and off with a steady pulse. Then the "A careful touch on the Wave Generator is necessary as we are dealing with the powers of the whole world here...." A concerted ahhhh swept through the crowd as the Space Wave Tapper shivered a bit, then rose slowly into the air. The demonstrator stepped back and the toy rose higher and higher, bobbing gently on the invisible waves of magnetic force that supported it. Ever so slowly the power was reduced and it settled back to said, putting a large price sign on the table. "For the complete set of the Atomic Wonder, the Space Tapper control box, battery and instruction book ..." At the appearance of the price Hawton was the only one left after the crowd had moved on. "Could you tell me how this thing works?" the colonel asked, coming forward. The demonstrator brightened up and picked up one of the toys. "Well, if you will look here, sir...." He opened the hinged top. "You will see the Space Wave coils at each end of the ship." With a pencil he pointed out the odd shaped in the bottom of the control box. Biff Hawton turned a very quizzical eye on the gadget and upon the demonstrator who completely ignored this sign of disbelief. "Inside the control box is the battery," the young man said, snapping it open and pointing to an ordinary flashlight battery. "The current goes through the Power Switch and Power Light to the Wave Generator ..." "What you mean to say," Biff fifteen cent battery goes through this coils in the model and absolutely nothing happens. Now tell me what really flies the thing. If I'm going to drop eighteen bucks for six-bits worth of tin, I want to know what The demonstrator flushed. "I'm sorry, sir," he stammered. "I wasn't trying to hide anything. Like any magic trick this one can't be really demonstrated until it has been purchased." He leaned forward and whispered confidentially. "I'll tell you what I'll do though. This thing is way overpriced and hasn't been moving at how it works. The boys in the shop will get a kick out of it," he tapped the winged rocket on his chest. "Now —what holds it up?" The demonstrator looked around through a tiny loop in the ceiling, this ring on my finger. When I back that." "All good illusions are simple," the colonel grunted, tracing the black thread with his eye. "As long as there is plenty of flimflam to distract the viewer." "If you don't have a black table, a black cloth will do," the young man good site, just see that the room in back is dark." "Wrap it up, my boy, I wasn't born gang were all missile men and they cheered and jeered as he hammed up the introduction. "Let me copy the diagram, Biff, I could use some of those magnetic waves in the new bird!" "Those flashlight batteries are cheaper than lox, this is the thing of the future!" Only Teddy Kaner caught wise as the flight began. He was an amateur magician and spotted the gimmick at once. He kept silent with professional courtesy, and smiled ironically as the rest of the bunch grew silent one and he had set the scene well. He almost had them believing in the Space Wave Tapper before he was through. When the model had landed and he had switched it off he couldn't stop them from crowding around the table. "Too bad," the head project physicist said, "I was hoping that a little Space Wave Tapping could help us out. Let me try a flight with it." "Teddy Kaner first," Biff announced. "He spotted it while you were all watching the flashing lights, only he didn't say anything." Kaner slipped the ring with the to step back. "You have to turn the switch on that's part of illusion—the spiel and the misdirection. I'm going to try this cold first, so I can get it moving tried it, which got a good laugh that made his collar a little warm. Someone lift the model only when the switch those toy ships for every brat within to people who would be interested?" the older man asked. "I think so, I caught a few Air Force officers and a colonel in missiles I remembered from the Bureau of Standards. Luckily he didn't recognize you spotted from the university." "Then the problem is out of our hands and into theirs. All we have to " What results?! These people weren't interested when we were hammering on their doors with the proof. We've patented the coils and can prove to anyone that there is a reduction in weight around them when they are operating...." "But a small reduction. And we don't know what is causing it. No one can be interested in a thing like to lift the weight of the generator. No one wrapped up in massive fuel consumption, tons of lift and such is going to have time to worry about a crackpot who thinks he has found a minor slip in Newton's laws." "You think they will now?" the young man asked, cracking his knuckles "I know they will. The tensile strength of that thread is correctly adjusted to the weight of the model. The thread will break if you try to lift the model with it. Yet you can lift the model—after a small increment of its weight has been removed by the coils. This is going to bug them to solve the problem or concern themselves with it. But it will nag at them because they know this effect can't possibly exist. They'll see at once that the magnetic-wave theory is nonsense. Or perhaps true? We don't know. But they will all be thinking about it and worrying about it. Someone is going to experiment in his basement—just as a hobby of course—to find the cause of the error. And he or someone else is going to find out what makes those coils work, or maybe a way to improve them!" "And we have the patents...." "Correct. They will be doing the research that will take them out of the massive-lift-propulsion business and into the field of pure space flight." "And in doing so they will be making us rich—whenever the time comes to manufacture," the young man said cynically. "We'll all be rich, son," the older "Believe me, you're not going to recognize this old world ten years from now." Transcriber's Note:

<question>:
What does the  Atomic Wonder Space Wave Tapper gadget do?

<options>:
A It can drive itself.
B It levitates in the air.
C It flies in the air.
D It can detect live in outer space.

<answer>:

B