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 AVENGER By STUART FLEMING Karson was creating a superman to fight the weird suffering, but I could recognize it. "You yourself have said it," I told him. "I am a being of logic, just as the beings who have invaded your planet are. I do not comprehend the I repeated it patiently. went to Earth, I would use your people to further my knowledge, just as the invaders do. I would have no reason to kill the invaders. They are more nearly kin to me than your people." Peter's eyes were dull, his limbs slumped. For a moment I thought that He waved his hands helplessly. "Gratitude?" he muttered. "No, you don't understand that, either." Then he cried suddenly, "But I am your friend, Robert!" arrangement: I did what Peter wished, so long as I did not actively want to do otherwise, because he had done things for me. Very well, then we must not go back. It was very simple, but I knew that he could not comprehend it. I tried to explain it to him, however. But he only stared at me, with and alien. It was I who had changed: something inside me was dead, like the machinery, and like Peter. an expression on his face that I had never seen there before, and that, One part of his brain had been shocked into its shell. It was hiding from the thing that had hurt it, and it refused to respond. But the other part was going calmly, lucidly on, quite without his volition. It considered the possibility that he had gone temporarily insane, and decided that this was probable. Relief washed over him, leaving him breathless. He was horrified, of course, but only abstractedly. For the moment he could only be glad that what he had seen was terrible reality rather than even more terrible illusion. INVADERS APPEAR IN BOSTON. 200 DEAD "The reason for this ... order must be apparent to all civilized peoples. For the Invaders have spared no part of this planet in their "Since the Invaders first appeared in Wood River, Oregon, 24 hours ago, they have not once acknowledged our attempts to communicate, or in any way taken notice of our existence as reasoning beings. They have done as they would with us. They have examined us, dissected us, driven us mad, killed us with no discernable provocation and this is are threatened, but our existence as a race. We must, and will, destroy the Invaders!" Peter sank back in his chair, the full shock of it striking him for the first time. mechanism to "Etaoin Shrdlu," principally because he hated double-talk. He mouthed the syllables, had to repeat them because he put an accent in the wrong place, and squeezed through the door as soon as it opened far enough to admit him. heartbeat they were gone. There were left only two blood-red, malignant monstrosities somehow defiling the air they floated in and below them, a pitiful huddle of flesh no longer recognizable as human beings. They were not dead, those men and women, but they wanted to be. Their bodies had been impossibly joined, fused together into a single obscene, floundering mass of helpless protoplasm. The thin moaning that went up from them was more horrible than any cry of agony. "The Invaders are here, citizens," the commentator was saying in a strangled voice. "Stay off the streets. Hide yourselves. Stay off the streets...." His voice droned on, but neither of them heard it. "Peter!" she said faintly. "Why do they broadcast such things?" any noncombatants, this time. Everybody in the world has to know about them, so that he can fight them—and then it may not be enough." other faint sounds that were no longer normal. Then, very near, a man screamed in a high, inhuman voice. The screamed dwindled into a throaty gurgle and died, leaving silence again. Peter's lips were cold with sweat. Tiny nerves in his face and arms range of vision. Peter forced himself forward another step. Little Harry Kanin, Lorelei's assistant, was crumpled in a corner, half supported by the broad base of an X-ray chamber. His face was flaccid and bloated. His glazed eyes, impassive yet somehow pleading, stared at nothingness straight ahead of him. The Invaders ignored Peter, staring expressionlessly down at Kanin. In a moment Peter realized what they were doing to him. He stood, paralyzed with horror, and watched it happen. There was a scream in his throat that would not come out. He was beyond fear, beyond agony. He turned to the still-hovering monsters and said in a terrible voice, "Why? Why?" ... raswilopreatadvuonistuwurncchtusanlgkelglawwalinom.... " "I can't understand," he cried wildly. "What do you want?" " ... morofelcovisyanmamiwurlectaunntous. the room. It was a scream to split eardrums a scream to wake the dead. Somebody said, "Doctor!" He wanted to say, "Yes, get a doctor. Lorelei—" but his mouth only He was right. All the nurses, and even Dr. Arnold, were evasive, but he kept asking them why he couldn't see Lorelei, and finally he wormed it sooner. "She was only suffering from ordinary shock," Arnold explained. "Seeing that assistant of hers—it was enough to knock anybody out, "But where is she?" Peter complained. "You still haven't explained why "But why?" Peter whispered. Arnold's strong jaw knotted. "We're hiding," he said. "Everything else has failed." It didn't take us long to find out we couldn't kill them. They didn't even take any notice of our attempts to do so, except once. That was "I wonder," Peter said shakily, "if I am strong enough to take it." we're riding a curve that ends in extinction fifty years from now. "They'll live, and we'll die, because they're a superior race. We're a million years too far back even to understand what they are or where they came from. Besides them, we're apes. There's only one answer." possible mutations, there's one that will save the human race. We can't fight staying alive. You'd have one chance in a million of staying beautiful. I couldn't stand that. I'd kill myself, and then humanity would die, too. You'd be their murderer." come back, Peter." he slumped down before them and listlessly closed the contact of the visiplate. He swung its field slowly, scanning for the last time the bare walls its slow, monstrous alchemy upon him. Peter waited until the changes animation of their crystal cells. One by one he allowed them to mature, and after weeks or years destroyed the monstrosities that came from the incubators. Time went by, meaninglessly. He ate when he was hungry, slept when his driving purpose let him, and worked unceasingly, searching for the million-to-one chance. Peter closed the diary. "The rest you know, Robert," he said. brain is as superior to mine as mine is to an anthropoid's. You solve instinctively problems that would take our mechanical computers hours sure. But now, the waiting is over. "They're still there, I'm sure of it—the people, and the Invaders. You can kill the Invaders, Robert." He looked at me, a little oddly, almost as if he had some instinctive knowledge of what was to come. But he went on swiftly, "On Earth we they are. You can understand them, and so you can conquer them." I said, "That is the reason why we will not go back to Earth." He stared at me, his jaw slack, his hands trembling. "What—what did

<question>:
Why did Robert choose to not return to Earth after Peter had told him that he was ready?

<options>:
A He wanted to stay with Peter, alone.
B His fear of the Invaders after hearing the story from Peter's diary
C His logic wouldn't allow him to fulfill the purpose
D He couldn't decipher the difference in killing the humans and the Invaders

<answer>:

C