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

<passage>:
As Ludovick writhed restlessly upon his bed, he became aware that someone had come into his chamber. "Ludovick," a soft, beloved voice whispered, "I have come to ask your help...." It was so dark, he could not see her As the vastly advanced guardians of mankind, the Belphins knew how to make a lesson stick—but whom? Only the Belphins were much in evidence. Only the Belphins had duties to perform. Only the Belphins worked. Ludovick stretched his own well-kept golden body and rejoiced in the knowing that he was a man and not a Belphin. Immediately afterward, he was sorry for the heartless thought. Didn't the Belphins work only to serve humanity? How ungrateful, then, it was to gloat over them! Besides, he comforted himself, probably, if the truth were known, the Belphins "You must warn as many Belphins as you can." "Then," she said dramatically, "you must approach The Belphin of Belphins himself." The Belphin. You're coming to in the darkness, the jewel swung madly on her presumably heaving bosom. "This is bigger than both of us. It's for Earth." He knew it was his patriotic duty to do as she said "He'd only make another. Don't you see, Ludovick, this is our only chance to save the Belphins, to save humanity.... But, of course, I don't have the right to send you. I'll go myself." Next morning, he set out to warn Belphins. He knew it wasn't much use, but it was all he could do. The first half dozen responded in much the same way the Belphin he had warned the previous day had done, by courteously acknowledging his solicitude and assuring him there was no need for alarm After that, they started to get increasingly huffy—which would, he thought, substantiate the theory that they were all part of one vast coordinate network of identity. Especially since each Belphin behaved as if Ludovick had been repeatedly annoying At last he gave up and wandered about the city for hours, speaking to neither human nor Belphin, wondering what to do. That is, he knew what he had to do to do it. He would never be able to reach The Belphin of Belphins. No human being had ever done it. Mieczyslaw and George had died trying to reach him (or it). Even though their intentions had been hostile and Ludovick's would be helpful, there was little chance he would be allowed to reach The Belphin with all the other Belphins against him. What guarantee was there that The Belphin would not be against him, too? And yet he knew that he would have to risk his life there was no help for it. He had never wanted to be a hero, and here he had heroism thrust upon him. He knew he could not succeed equally well, he knew he could not turn back, for his Belphin teacher had instructed him in the meaning of duty. It was twilight when he approached the Blue Tower. Commending himself to the Infinite Virtue, he entered. The Belphin at the reception desk did not give off the customary smiling expression. In fact, he seemed to radiate a curiously apprehensive aura. "I must see The Belphin of Belphins. I must warn him against the Flockharts." "I don't trust you or your brothers. I must see The Belphin himself." "The Belphin of Belphins did things for us," Ludovick countered. "You are all only his followers. How do I know you are Without giving the creature a chance to answer, he strode forward. The Belphin attempted to bar his way. Ludovick knew one Belphin was a myriad times as strong as a human, so it was out of utter futility that he struck. The Belphin collapsed completely, flying apart in a welter of fragile springs and gears. The fact was of some deeper significance, Ludovick knew, but he was too numbed by his incredible success to be able to think clearly. All he knew was that The Belphin would be able to explain things to him. A staircase spiraled up ahead of him. A Belphin was at its foot. Behind him, a barrier iridesced. But Ludovick destroyed the thing before it could say anything further, and he passed right through the barrier. He had to get to the top and warn The Belphin of Belphins, whoever or whatever he (or it) was, that the Flockharts had a secret weapon which might be able to annihilate it (or him). Belphin after Belphin Ludovick destroyed, and barrier after barrier he penetrated until he reached the top. At the head of the stairs was a vast golden door. Ludovick smiled and set his nearly full glass down on a plinth. "You could hardly call the Belphins foreigners But all Ludovick knew was that he had to get to The Belphin within and warn him. He battered down the door "Go no further, Ludovick Eversole!" a mighty voice roared from within. "To open that door is to bring disaster upon your race." "They say," the uncle continued, impervious to Ludovick's unconcealed dislike for the subject, "that there's really only one Belphin, who lives in the Blue Tower—in a tank or something, because he can't breathe our atmosphere—and that the others are a sort of robot he sends out to do his work for him." The Belphin of Belphins died in Ludovick's arms. He was the last of his race, so far as Earth was concerned, for no more came. If, as they had said themselves, some outside power had sent them to take care of the human race, then that power had given up the race as a bad job. If they were merely exploiting Earth, as the malcontents had kept suggesting, apparently it had proven too dangerous or too costly a venture. Shortly after The Belphin's demise, the Flockharts arrived en masse. "We won't need your secret weapons now," Ludovick told them dully. "The Belphin of Belphins is dead." Ludovick looked at him through a haze of tears. "But I killed The Belphin. I didn't mean to, but ... they must hate me!" "He said the Belphins rule through the power of love." "Because she is not The Belphin-slayer," the uncle said, dragging him out. "Besides, she loves you. Come on, Ludovick, be a man." So they hauled him off to the wedding and, amid much feasting, he was married to Corisande. In the second place, Ludovick could never forget that, when Corisande had sent him to the Blue Tower, she could not have been sure that her secret weapon would work. Love might on the other hand, could he stand idly by and let those neighbors attempt to destroy the social order? Deciding that the greater good was the more important—and that, moreover, it was the only way of taking Corisande away from all this—he went in search of a Belphin. That is, he waited until one glided past and called to him to leave the walk. Ludovick knew, of course, that the Belphin used the word But Ludovick could not be happy. He wasn't precisely sad yet, but he was thoughtful. Of course the Belphins knew better than he did, but still.... Perhaps they underestimated the seriousness of the Flockhart conspiracy. On the other hand, perhaps it was he who was taking the Flockharts too seriously. Maybe he should investigate further before doing anything rash. He lay down to sleep that night beset by doubts. If he told the Belphins about the conspiracy, he would be betraying Corisande. As a matter of fact, he now remembered, he

<question>:
Why was Ludovick able to get to the Belphin of Belphins?

<options>:
A He used Corisande's uncle's secret weapon
B He destroyed the machines
C He had only love for Belphin
D His need was high enough

<answer>:

C