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

<passage>:
HUNTED the next ship for Earth." By ROBERT SILVERBERG The planet itself was tough enough—barren, desolate, forbidding "Go back? "I never bothered to find out their names," Ledman Death to all Terrans! said casually. "They were we're going back out there to Val. "The surest way to die out here on Mars is to give up." I reached over and turned up the pressure on her finish that search-pattern. "Let's keep moving," I told Earth needs uranium, honey, and I know you'd never be point, because Val didn't lie all my fault, too. Val's usually "Let's get moving, fellow airlock, smiling. THE END Transcriber's Note: that some grease monkey back at the Dome was at fault—whoever it was who had failed There had been a pattern of disappearances on the desert. I could think of six, eight It was beyond her to see names now. None of them "You've been hunting But no Why? What've they ever done to she blamed it all on of the Martian desert. We'd genius who had a motto: Ron?" Val pleaded. "Maybe we're crazy to keep on searching When Val's tired and overwrought HEROES desert. That's the only sport I But I'm determined to drive the Geigs—and UranCo—off Mars. Eventually I'll scare you all away." "Just pick us off in the desert?" well fortified. I've devoted years to building it. And I'm "Try to keep going, Val." "Come on, kid. Remember—we're doing this for Earth. We're heroes." years to this. Ever since—ever since I landed here on Mars." "What are you going to do with us?" Val finally asked, we dump this guy I'm sacking for the pay, Val." for their constant undercurrent Even though the Martian on the infinitely safer desert. Earth's, I was starting to been really rough on Val with tire, and I knew it must have snapped. "Well, let me show you. You're on Mars hunting uranium, right? To mine and ship the radioactives back to Earth to keep the atomic engines going. Right?" you volunteer for the Geig "We're not heroes—we're "We volunteered to come to Mars," Val said irrelevantly. much inflamed by the idea of coming to Mars to help in the "Ah—two young heroes," Ledman said acidly. "How search for uranium as I was. doing. She had been just as could do as individuals to We knew the pay was poor, Earth going. And we'd always had a roving foot, both of us. No, we had decided together that great accident—killing to come to Mars—the hundreds, injuring thousands more, sterilizing forty miles would. How could I forget of Mississippi land—when way we decided together on everything. Now she was I was there to sign a new the contract, but I got a good dose of radiation instead. Not enough to kill me," he said. "But why kill us Geigs? Mars, until I recalled that I had nothing to do with it." "You're just in this by accident," he said. "You see, after We the explosion and the amputation, the Val who had so enthusiastically suggested we join hadn't. In fact, she had come up with the idea before I did. "You're a very sick man, Ron?" Val asked sleepily. to fasten down the engine Mars, lost myself, built this Dome, and swore to get even. There's not a great deal of uranium on this planet, but had been particularly close Mars after all. But, I reminded myself, someone on red blood corpuscles." I looked down at Valerie's sleeping form, and thought of down over one eyebrow, and it seemed hard to believe that we'd exchanged Earth and all it held for us for the raw, untamed struggle that was Mars. But I knew I'd do it again, if I had the chance. It's because about his threat to wipe out had. Heroes? Hell, no. We the entire Geig Corps, since the needle into his arm. My eyes widened. It was can succeed?" I taunted him. "Really think you can kill every Earthman on Mars? Of all the insane, cockeyed—" Val's quick, worried head-shake married couples, working in I'd never forget it. No one we volunteered. "You're sick, Gregory Ledman," Val said quietly. once again to wake Val. "You've conceived an impossible scheme of revenge and now you're taking it out on "Why don't you do something? for, Ron?" to turn you loose outside, right after—" " a spider's web is for a trapped fly. It wasn't Martians that had done it. There weren't any Martians, hadn't been for a million years. It was some Earthman who had bound us. I rolled my eyes toward Val, and saw that she was what was wrong with Val. convinced me. I saw Val's "Ron—" spacesuit and a fishbowl helmet, all but the face area weren't attached to his back as expected, though. They were strapped to the odd. I thought I knew everyone on sparsely-settled Mars. Somehow I'd missed him. What shocked me most was spacesuit ended neatly at the "Teamwork," Val said. She and a very efficient-looking blaster was in his right. "I didn't want to disturb scratch up the side of Val's are you?" "You'll find out soon enough," he said. "Suppose to make trouble." Val and I oxysuits. sent back to Earth." " No! don't want to face them again—not "They'll help you on Earth. "What's going on, Ron?" Val asked in a low voice as we out. "I hate all of them." "I know," I said sarcastically. "You're just all full of around on Earth for as much off for Mars without a moment's delay, didn't you? You hated Earth so much you why. I wondered why we had ever left Earth. The answer to that came to me quick enough: we had to. Earth needed radioactives, and the only way to get them was to get out and look. The great atomic wars of the late I had no muscles to fit them to." "You left Earth too quickly," them back together again. Val said. They had used their atomics for fuel. the wall of the Dome at blaster-point. But then I remembered of events that led Val and me to end up as a madman's prisoners, have added Val to the number on Mars. With every on Earth, we had tried other possibilities. All sorts of he'd killed twelve source of uranium mined dry Geigs—or more—and would schemes came forth. Project had he had the chance. Earth. But you decided to channel everything out as revenge." "I still don't believe it—those to tide us over until then. In a Sea-Dredge was trying to get uranium from the oceans. In a great atomic civilization. So, Mars. There's not much "Haven't you wondered how I managed to break the tangle-cord when I kicked you uranium on Mars, and it's not over?" "Yes—human legs aren't strong enough to break tangle-cord easy to find or any cinch to gave Val the blaster and slipped Mars, combing for its uranium deposits. And here we are, I thought. out on the face of out of my oxysuit. "Look," I said. I pointed to two hummocks on the Val got him into his suit, and let's go. Between the psychs you'll be a new man inside of a year." "But I'm a murderer!" "That's right. And you'll be sentenced to psych adjustment. When they're finished, Gregory Ledman the killer will be as dead as if they'd electrocuted you, but there'll one side of the airlock, uttered a few words keyed to his "Let's get back to the Dome

<question>:
Why have Val and Ron joined a mission on Mars?

<options>:
A to locate a new source of fuel
B to restore Earth's depleted fuel reserves
C to determine if the planet can be colonized
D to identify the source of recent astronaut murders

<answer>:

B