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

<passage>:
blood," old Dunbar told the space-wrecked, desperate men. "Only one way to go, where we can float down through the the red rim around it." But Dunbar's eyes were old and uncertain. How could they believe in his choice when every star in this forsaken individual rockets, held together by an awful pressing need for each other and by the "gravity-rope" beam. Dunbar, the oldest of the four, an old space-buster with a face wrinkled like a dried prune, burned by cosmic rays and the suns of worlds so far away they were scarcely credible, had taken command. Suddenly, Old Dunbar had known where they were. Suddenly, Dunbar knew where they were going. They could talk to one another through the etheric transmitters inside Four men, thought Russell, held together by an invisible string of gravity, plunging through a lost pocket of hell's dark where there had never been any sound or life, with old Dunbar the first in line, taking the lead because he was older and knew where he was and where But Russell knew it and he'd admitted it from the first—that old Dunbar was as crazy as a Jovian juke-bird. recognizable pattern. But Dunbar knew. And Russell was looking at Dunbar's suit up ahead, watching it more and more intently, thinking about how Dunbar looked inside that suit—and hating Dunbar more and more for claiming he knew when he didn't, for his drooling optimism—because he was taking them on into deeper darkness and Sometimes Russell thought of other things besides his growing hatred Dunbar. Out here, a human being is the smallest thing of all. He thought then of what Dunbar would say to such a thought, how Dunbar would laugh that high piping squawking laugh of his and say that the human being was bigger than the Universe itself. Dunbar had a big answer for every little thing. When the four of them had escaped from that prison colony on a sizzling hot asteroid rock in the Ronlwhyn system, that wasn't enough for Dunbar. Hell no—Dunbar had to start talking about a place they could go where they'd never be apprehended, in a system no one else had ever heard of, where they could live like gods on a green soft world like the Earth had been a long time back. And Dunbar had spouted endlessly about a world of treasure they would find, if they would just follow old Dunbar. That's what all four of them had been trying to find all their lives in the big cold grabbag of eternity—a rich star, a rich far fertile star where no one else thought. No one for God only knew how many of millions of light years away could see or care. Still—we might have a chance to live, even now, Russell thought—if it weren't for old crazy Dunbar. They might have a chance if Alvar and Johnson weren't so damn lacking in self-confidence as to put all their trust in that crazed old Russell said. "That's right, boys!" yelled old Dunbar in that sickeningly optimistic voice. Like a hysterical old woman's. "Just about in the sweet dark old middle." life on it, Dunbar ... the only one we can live on?" Russell asked. "That's right! That's right," Dunbar yelled. "That's the only one—and it's a paradise. Not just a place to live, boys—but a place you'll have trouble believing in because it's like a dream!" Dunbar?" Russell asked. Keep the old duck talking like this and maybe Alvar and Johnson would see that he was cracked. "Yeah," said Alvar. "You still say that, Dunbar?" "No life, boys, nothing," Dunbar laughed. "Nothing on these other worlds but ashes ... just ashes and iron and dried blood, dried a said that one had a red rim, Dunbar, and I wanted to believe it. So now maybe we're all seeing a red rim that was never there." Old Dunbar laughed. The sound brought blood hotly to Russell's face. "We're heading to the right one, boys. Don't doubt me ... I been here. We explored all these sun systems. And I remember it all. The second I'd break away, go it alone to the right sun, Russell thought—but I'd never make it alone. A little while out here alone and I'd be nuttier than old Dunbar will ever be, even if he keeps on getting nuttier all the time. Somewhere, sometime then ... Russell got the idea that the only way was to get rid of Dunbar. You mean to tell us there are people living by that red-rimmed sun," Russell said. "Lost people ... lost ... who knows how long," Dunbar said, as the always spring, always spring, boys, and the music plays all night, every night of a long long year...." Russell suddenly shouted. "Keep quiet, Dunbar. Shut up will you?" Johnson said. "Dunbar—how long'll it take us?" "Six months to a year, I'd say," Dunbar yelled happily. "That is—of our hereditary time." "What?" croaked Alvar. Johnson didn't say anything at all. Russell screamed at Dunbar, then quieted down. He whispered. "Six months to a year—out here—cooped up in these damn suits. You're crazy as hell, Dunbar. Crazy ... crazy! Nobody could stand it. We'll all be crazier than you are—" "We'll make it, boys. Trust ole' Dunbar. What's a year when we know a whole lot of it, and I know. In the old days—" "The hell with the old days," screamed Russell. "Now quiet down, Russ," Dunbar said in a kind of dreadful crooning whisper. "You calm down now. You younger fellows—you don't look at you and takes you away to a museum...." "Shut up!" Johnson yelled. Dunbar laughed. "Boys, boys, don't get panicky. Keep your heads. Just stick to old Dunbar and he'll see you through. I'm always lucky. Only one way to go ... an' that's straight ahead to the sun with the have red rims around them. Dunbar—" A pause and no awareness of motion. Dunbar laughed. "Sure, they all maybe have a touch of red, but it isn't the same, boys. I can tell the difference. Trust me—" easy. There was a flash of burning oxygen from inside the suit of Dunbar. If he'd aimed right, Russell knew the fire-bullet should have pierced Dunbar's back. Now the fire was gone, extinguished automatically by units inside the suit. The suit was still inflated, self-sealing. Nothing appeared to have changed. The four of them hurtling on together, but inside that first suit up there on the front of the gravity rope, Dunbar was dead. He was dead and his mouth was shut for good. Dunbar's last faint cry from inside his suit still rang in Russell's ears, and he knew Alvar and Johnson had heard it too. Alvar and Johnson both called Dunbar's name a few times. There was no answer. "Russ—you shouldn't have done that," Johnson whispered. "You shouldn't have done that to the old man!" him because we didn't have the strength to make up our own minds. Why does a crazy man's laugh sound so good when you're desperate and don't know what to do?" once you're going, you never stop ... and I guess there isn't any other body to pull him off his course. And what will time matter to old Dunbar? Even less than to us, I guess. He's dead and he won't care." "Ready," Johnson said. "I'll cut off the gravity rope." Russell couldn't say anything. He stared at the endless void which now he would share with no one. Not even crazy old Dunbar. And old Dunbar shooting right on ahead. And all three of them dwindling and dwindling and blinking out like little lights. Fading, he could hear their voices. "Each to his own star," Johnson

<question>:
What fuels Russell's loathing of Dunbar?

<options>:
A Dunbar's optimism
B Dunbar's age
C Dunbar's delusions
D Dunbar's laugh

<answer>:

A