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

<passage>:
By WILLIAM L. BADE Extensive research did not uncover any evidence that To the men of the future, the scientific why have held the number at that." "Birth control," Maitland scoffed. "How do you make it work—secret police?" in finding out what the canals are? Or what's under the clouds of he remembered what had happened during Where was he? Who had brought him here? For what purpose? He thought he knew the answer to the last of those questions. As a member of the original atomic reaction-motor team, he possessed information that other military powers would very much like to obtain. It was absolutely incredible that anyone had managed to abduct him from She smiled. "In a room downstairs there is the head of a lion. Swarts the heavily guarded confines of the Reservation, yet someone had done it. How? what from the human race, or built apparently from an aluminum alloy, somehow gave the impression Man . We are terribly interested in what can be done with people. Our scientists, like Swarts, are studying human rather than nuclear reactions. We are much more fascinated by the life and death of cultures than by the expansion or contraction of the earnest 12th Century crusader, deposited by some freak of nature into in vain that the atomic bomb offered a means of finally destroying the infidel.... He looked out at the peaceful vista of river and prairie. The character Where the devil could this place be? And—muscles tightened about his his attention. Pressing his nose against the window, he strained his he and showed striking muscular development, like persons who had trained for years with weights. They vanished below his field of view, presumably into the building. This man was intelligent, Maitland decided, and extremely sure of Impassively, the man said, "My name is Swarts. You want to know where you are. I am not going to tell you." He had an accent, European, but otherwise unidentifiable. Possibly German. Maitland opened his mouth to protest, but Swarts went on, "However, you're free to do all the any way, provided you cooperate. And you can forget the silly idea that we want your childish secrets about rocket motors." Maitland's heart jumped. "My reason for bringing you here is altogether different. I want to give you some psychological tests...." your tests to." Briefly, then, Swarts did smile. "They won't find you," he said. "Now, After that outlandish cell, Swarts' laboratory looked rather "Lie down," Swarts said. When Maitland hesitated, Swarts added, "Understand one thing—the more you cooperate, the easier things will be for you. If necessary, I will use coercion. I can get all my results against your will, if I must. I would prefer not to. Please don't make me." "What's the idea?" Maitland asked. "What is all this?" Swarts hesitated, though not, Maitland astonishedly felt, to evade an answer, but to find the proper words. "You can think of it as a lie detector. These instruments will record your reactions to the tests I If Swarts was irritated, he didn't show it. "That was the first test," "I see," Swarts said. "You want to find out what you're up against." his chest, hips, knees, ankles, and arms, and Swarts was tightening a So—Maitland thought—Swarts could record changes in his skin The question was, what were the stimuli to be? "Your name," said Swarts, "is Robert Lee Maitland. You are thirty-four question you about your work "I do not know everything about you—yet. And I'm testing the equipment, calibrating it to your reactions." He went on, "Your favorite recreations are chess and reading what you term science Swarts was chuckling. "I really hit a semantic push-button there, why There were three questions for which he required answers before he Where was he? Who was Swarts? What was the purpose of the "tests" he was being given? It was possible, of course, that this was all an elaborate scheme for getting military secrets, despite Swarts' protestations to the contrary. Maitland frowned. This place certainly didn't have the appearance of a military establishment, and so far there had been nothing to suggest the kind of interrogation to be expected from foreign intelligence officers. It might be better to tackle the first question first. He looked at the Sun, a red spheroid already half below the horizon, and tried to have to worry any more about military secrets, or who Swarts was. Those questions were irrelevant now. And now he could accept the psychological tests at their face value most likely, they were what they purported to be. Only one question of importance remained: He grimaced in the darkness, an involuntary muscular expression of jubilation and excitement. The the greatest adventure imaginable to 20th Century man. Somewhere, out there under the stars, there must be grand glittering he way of breaking down Swarts' reticence. He would have to make the man realize that secrecy wasn't necessary in this case. And if Swarts still wouldn't talk, he would have to find a way of forcing the issue. The fellow had said that he didn't need cooperation to get his results, shoulder, "You will have to ask Swarts about that. I cannot tell you." Swarts came half an hour later, and Maitland began his planned offensive. "What year is this?" Swarts' steely eyes locked with his. "You know what the date is," he "Come on," Swarts said patiently, "let's get going. We have a lot to Wordlessly, Maitland climbed to his feet, preceded Swarts to the the instruments, making no resistance at all. When Swarts started test—Maitland began the job of integrating "csc It was a calculation which required great concentration and frequent tracing back of steps. After several minutes, he noticed that Swarts It took Swarts nearly twenty minutes to set up the new apparatus. He more. He brooded over the damnable stupidity and short-sightedness of Swarts in standing by his silly rules and not telling him about this forehead, and he began to curse. Swarts! How he hated.... eyes and Swarts was standing over him, white-lipped. Maitland swore at "All right," Swarts said. "A.D. 2634." "I really haven't the time to waste talking irrelevancies," Swarts said Maitland considered a moment, then nodded. Swarts lowered the projector he was seeing visions of Venus and the awesome beauty of Saturn. In his mind, he circled the Moon, and viewed the Earth as a huge bright want, even from Swarts, and I have not been able to get even a little She shrugged. "Swarts says that I want to go back to the Dark Age of altogether like the Norwegians of my time." His fear that she would be offended proved to be completely or Asiatic." She giggled. "Swarts' ancestors from your time must be Lassisi Swarts." Maitland wrinkled his brow. "Afrikander?" they had developed technology while the rest of the world lost it. They had a tradition of white supremacy, and in addition they were terrified it was founded on the slaughter of one and a half billion human beings. That went into the history books as the War of Annihilation." "So many? How?" "They were clever with machines, the Afrikanders. They made armies of the technicians who built the Machine Army set up our robot production system, and today no human being has to dirty his hands raising food or manufacturing things. It could never have been done, "No. Intermarriage. Racial blending. There was a psychology of guilt She frowned and shook her head. "What does that mean—space travel?" He was gripping the edge of the bed now, glaring at her. "A civilization that could discover time travel and build robot factories why happened? Why don't men want the planets any more?"

<question>:
What was the nature of Swarts’ research?

<options>:
A Understanding cognitive functioning of astro-physicists
B Understanding thought processes of people with desire to travel to Earth’s moon
C Determining how to spark desire for space travel in the population
D Stealing military secrets

<answer>:

B