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

<passage>:
era than to have them shipped from the future—he seldom went ashore, and then only at the urging of a newly assigned cousin anxious to see When he was pressed by the current cousin to make a land visit kin—but by those who hadn't been born yet? disappeared and Ninian came to take care of him. Mothers had a way of disappearing around those parts and the kids were often better the descendants were Martin showed his work in Italy, so that the cousin could be Sometimes he wondered who Ninian really was. Obviously that story about her coming from the future was just a gag. Besides, if she really was his great-great-grand-daughter, as she said, why would she tell him to call her " Aunt Ninian the current cousin—who was passing as his nephew by now. instead of mopping up the floor with him. "But I can't understand," he would say, keeping his face straight. "Why do you have to come from the future to protect me against your cousin Conrad?" conversation, anyhow. "When he does show up, I'll protect you," the cousin vowed, touching his ray gun. "You haven't a thing to worry about." voyaged to southern waters. There was a war in the south and they hid time. The Interregnum passengers from the future, plus one bored and aging contemporary. She to know what gave. They tried talking to Ninian, but she certainly knew Ninian bought one of those smallish, almost identical houses that Raymond. From time to time, there were other visitors—Uncles Ives and Bartholomew and Olaf, Aunts Ottillie and Grania and Lalage, and many more—all cousins to one another, he was told, all descendants of his. From Ninian and her cousins, there was only an impersonal kindness. them were insane, or what Ninian had told him at first was the truth. They came from the future. When Martin was sixteen, Raymond took him aside for the talk Ninian had the not so intelligent life-forms on the other planets," Raymond "I've told you—our world is precisely the same as this one!" Raymond snapped. "We just come a couple of centuries or so later, that's all. But remember, our interests are identical. We're virtually the same past and think in the future. his descendants. They were all exceedingly handsome and cultivated he had discovered that Raymond was perhaps the most intelligent of the the fact that our great-grandfather discovered the super-drive, we might never have reached the stars. Which is ridiculous—his feeling great-grandchildren, but a great-grandchild can hardly be held "Oh, I do!" Martin said. He had pieced the whole thing together for himself long since, but he wanted to hear how Raymond would put it. "Unfortunately, Professor Farkas has just perfected the time transmitter. Those government scientists are so infernally officious—always inventing such senseless things. It's supposed to be hush-hush, but you know how news will leak out when one is always desperate for a fresh topic of conversation." Anyhow, Raymond went on to explain, Conrad had bribed one of Farkas' assistants for a set of the plans. Conrad's idea had been to go back in time and "eliminate!" their common great-grandfather. In that way, there would be no space-drive, and, hence, the Terrestrials would never get to the other planets and oppress the local aborigines. a rush. "I wormed the whole thing out of him and all of us—the other cousins and me—held a council of war, as it were, and we decided it was our moral duty to go back in time ourselves and protect you." He beamed at Martin. The boy smiled slowly. "Of course. You had to. If Conrad succeeded in cousins possessed to a consternating degree. he had learned long ago that nobody did anything for nothing. But saying so was unwise. "We bribed another set of plans out of another of the professor's night and day, he would never be able to carry out his plot. So we made our counter-plan, set the machine as far back as it would go—and here we are!" course Ninian But Raymond rushed on: "Soon as Ninian goes and I'm in full charge, exile," Raymond explained, "even though our life spans are a bit longer which, he felt, would increase its efficiency. But still he was dubious. "Maybe it'll work on someone coming from outside this house time ?" "Never fear—it has a temporal radius," Raymond replied. "Factory guarantee and all that." "Just to be on the safe side," Martin said, "I think I'd better have When it came time for the parting, it was Ninian who cried—tears at at understanding his descendants, far better than they at understanding that she'd come see him again. She never did, though, except at the very last. Raymond and Martin moved into a luxurious mansion in a remote area. The dozen years later, they weren't touched. Martin was never sure whether descendants were exceedingly inept planners. from the future, all available artifacts were antiques. Otherwise, stood in the front hall and present them to a local museum, because several times he fancied he saw them move. He also became an adept with the ray gun and changed the surrounding landscape quite a bit with it, until Raymond warned that this might lead Conrad to them. least twenty of the cousins came back through time to hold one of "Don't be a fool, Grania!" Raymond snapped. "Well, Martin, have you none of us knows a thing about science. But it could happen. Subconscious osmosis, if there is such a thing. That way, you might invent something ahead of time. And the fellow we got the plans from particularly cautioned us against that. Changing history. Dangerous." "Might mess up our time frightfully," Bartholomew contributed, "though, their times." difference in history. There were so many of them all through the ages." Cousin Ives—now that Martin was older, he was told to call the descendants cousin which Martin christened The Interregnum . They traveled about from sea to ocean and from ocean to sea, touching at various ports and making trips inland. Martin saw the civilized world—mostly in fragments nearly intact semi-civilized world and the uncivilized world, much the The other cousins appeared to find the yacht a congenial head-quarters, largely because they could spend so much time far away from the they never moved back to land. Martin spent the rest of his life on The Interregnum there was no valid reason why an ocean should stop a traveler through time. More cousins were in residence at once than ever before, because they came for the ocean voyage. They spent most of their time aboard ended in a brawl, because one cousin was sure to accuse another of then Ives would tell Martin of the future world he had come from. The picture drawn by Raymond and Ninian had not been entirely interbred aristocracy, to which Martin's descendants belonged by virtue of their distinguished ancestry. "Not only natives livin' on the other worlds," Ives said as the two He always felt that if any of the cousins could have come to realize been Ives. However, when the yacht touched at Tierra del Fuego one bitter winter, Ives took a severe chill. They sent for a doctor from the future—one of the descendants who had been eccentric enough to continent, a hundred years or more before the date of his birth. A great many of the cousins turned up at the simple ceremony. All were cousin from the future The Interregnum voyaged to every a while, Martin couldn't tell one from another. Cousin after cousin All the cousins were young, for, though they came at different times in his life, they had all started out from the same time in theirs. Only the young ones had been included in the venture their elders.

<question>:
How did Ninian, Raymond, and the other cousins go back in time?

<options>:
A They bribed the assistant for the plans and blackmailed or tortured someone to build the time transmitter for them.
B Professor Farkas' assistant sent them back in time using the time transmitter after they gave him a bribe.
C They bribed the assistant for the plans and hired a gadget enthusiast to build the time transmitter for them.
D Professor Farkas sent them back in time with the time transmitter.

<answer>:

A