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

<passage>:
Every writer must seek his own Flowery Kingdom in imagination's wide demesne, and if that search can begin and end on Earth his problem has been greatly simplified. In post-war Japan Walt Sheldon has found not only serenity, but complete freedom to write undisturbed about the things he treasures most. A one-time Air Force officer, he has turned to fantasy in that the small people with their by ... Walt Sheldon The tiny spaceship had been built for a journey to a star. But its small, mischievous pilots had a rendezvous with destiny—on Earth. I must admit that at first I wasn't sure I was hearing those noises. It was in a park near the nuclear propulsion center—a cool, quick eyes and clever fingers could "you will not be forgotten by the leprechauns. If we ever meet again, upon another world perchance, you'll find our friendship always eager and ready." it came from the rocket about putting the first moon rocket become convinced they could of ours, which were still in the undeveloped and so keep my part of the bargain." "I'll not be needing the gold," I said. never "What's this now?" "I'll not be needing it," I repeated. "I don't feel it would be right to take it for a service of this I see I shall have to explain this, of nuclear explosion—which is what the drive amounts to despite the fact that it is simply water in which nuclear salts have been previously to weary you. Perhaps you had better take my word for it that without this equation—correctly stated, mind you—mankind would be well advised not to make a first trip to the moon. And all this talk of coefficients and equations sits strangely, you might had given them the wrong equation, of course. They would never get their spaceship to work now, and later, if they tried to spy out the right information I would take special But I am, after all, a scientist. If I the advantage of being able to see them. As for our own rocket ship, it should be well on its way by next St. Patrick's Day. For I had indeed I would hardly have found myself engaged in vital research at the do without Keech's pot of gold, though it would have been pleasant to be truly rich for a change. There was no sense in cheating him out of the gold to boot, for leprechauns are most clever in matters of this sort and he would have had it back soon enough—or else made it a burden in some way. Indeed, I had done a piece of work greatly to my advantage, and also to the advantage of humankind, and when a man can do the first and include the second as a fortunate byproduct it is a most happy accident. For if I had shown the little people how to make a spaceship they They were building something in would have left our world. And this world, as long as it lasts—what be seen here in America. I had "Come along now, people!" said this crotchety one, looking straight at me. "Stop starin' and get to never seen them so busy, either. would it be in that event? I ask you more likely to blow ourselves to Kingdom know he can't see nor hear us!" foreman of the leprechauns—if Oh, it was good to hear the rich for your lives!" And they all began running, in behind the trees and bushes, and a sloping embankment nearby. "No, wait!" I said. "Don't go away! I'll not be hurting you!" They continued to scurry. I knew what it was they feared. "I don't intend catching one of you!" I said. "Come back, you daft little creatures!" But the glade was silent, and they had all disappeared. They thought I wanted their crock of gold, of course. I'd be entitled to it if I could catch one and keep him. Or so the legends affirmed, though I've wondered often about the truth of them. But I was after no gold. I only wanted tongue. I was lonely here in America, even if I had latched on to a fine job of work for almost shamefully generous pay. You see, in a place as full of science as the nuclear propulsion course it was a spaceship, or a and workable. I shook my head in wonder, then stepped back from the spaceship and looked about the glade. I knew blueprint stage. I knew that if I could just once hear the old tongue again, and talk about the old things, I might be able gold is delivered to your rooms tonight, spaceship, and this time I struck it and talk to me, I'll wreck this spaceship returned to the Island." He shook his head and remained it if you'll go away and leave us to our work." and glanced at the spaceship. group of little people be building a spaceship here in America—out in this lonely place?" a spaceship. I was surprised enough a spaceship at first glance! Well, I spaceship when I see one?" I said. "Invited by the American government to work on the first moon rocket here at the nuclear propulsion "How?" I asked. my pouch. "Well, now," he said, "first of all you're no doubt surprised to find us here in America." "I am surprised from time to "We had to come here," said Keech, "to learn how to make a spaceship." "A spaceship, now," I said, unconsciously "Leprechauns are not really mechanically knows." "Myself included," I agreed. "Then why do you need a spaceship?" "Well, if I may use an old expression, we've had a feelin' lately that we're not long for this world. Or let me put it this way. We feel the world isn't long for itself." "It's very simple. With all the super weapons you mortals have developed, there's the distinct possibility you might be blowin' us all up in the process of destroying yourselves." "There "Well, then, as I say," said Keech, "the little people have decided to leave the planet in a spaceship. Which we're buildin' here and now. We've spied upon you and learned how to do it. Well—almost how to do it. We haven't learned yet how to control the power—" "Hold on, now," I said. "Leaving the planet, you say. And where would you be going?" "There's another committee make the ship, and proceed with its construction. Naturally, we didn't understand all of your high-flyin' science, but some of our people are pretty clever at gettin' up replicas thought it was by the Russians. There's one thing which puzzles "It may be we never crossed your path. It may be you can only see us when you're thinkin' of us, and of What's important is for us to get our first ship to workin' properly and then we'll be on our way." "Well, then, it may be that you can help us—now that you know need it right now, if we're to make our ship move." "And you want me to help you with this?" humans! I knew it! Well, Mr. Houlihan, I'll give you reason enough. The pot o' gold, Mr. Houlihan!" Nor is it actually in an earthen crock. But there's gold, all right, enough to make you rich for the rest of your life. And I'll make you a proposition." "Go ahead." "We'll not be needin' gold where we're goin'. It's yours if you show us how to make our ship work." "Well, now, that's quite an here—and see you're not slow as ship's drive and see what we can see." was out we had half the spaceship "Over here, now! All right, bring those electrical connections over but Keech and his people made a was comfortable enough. Every once in a while someone from the town or the center itself would pass by, and stop to watch me. But of course they wouldn't see the leprechauns or anything the leprechauns had made, not being believers.

<question>:
What motivated the leprechauns to build a spaceship?

<options>:
A They desire to seek and add more riches to their already expansive collection
B They believe that humans' obsession with technology will make the world inhabitable
C They fear that their race will soon become extinct due to population decline
D They wish to transport their riches to another location where humans will never steal it

<answer>:

B