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

<passage>:
"... And I don't know how long I sat there after I found the water." He looked at the Goldburgian device he had made out of wire and tubing. remembered that, of course, I remembered that it can be separated with electricity. So I built this thing. Australia. Evans was a prospector, and like all prospectors, a sort of jackknife geologist, selenologist, rather. His tractor and equipment cost two hundred and fifty thousand dollars. Fifty thousand was paid for. The rest was promissory notes and grubstake shares. When he was broke, which was usually, he used his tractor to haul uranium ore and metallic sodium "I don't need rescuing, man," Evans said. Jones stared at him blankly. "You might let me have some food," Evans continued. "I'm getting short of that. And you might have someone send out a mechanic with parts to he had a fortune in chromium. The chromite petered out in a month and a half, and he was lucky to break even. "Well, it was to rescue you that I came." "Sure, man, I've thousands of tons of water here. It's the richest mine on the Moon!" THE END make it. By careful rationing, he could probably stretch his food out to more than a month. His drinking water—kept separate from the water in sixteen days. When he saw the wrecked turbine, he knew that he wouldn't carefully measured there was a four-day reserve. By diligent conservation, he might make it last an extra day. Four days reserve—plus one is five—plus sixteen days normal supply equals twenty-one days to live. the reactor—might conceivably last just as long. But his oxygen was too position. "Batteries must be dead," he told himself. He fumbled for a while, until he found a small flashlight. By the light of this, he reinspected the steam system, and found about three gallons used. It was one day's supply if used wastefully. It was ostentatious luxury for a man with a month's supply of water and twenty-one days to live. was passing through them. This was to allow the air-conditioning system to function properly, and to prevent air loss in case of the highly improbable meteor damage. McIlroy thought that on the whole, he was disobeying his own orders no more flagrantly than anyone else in the McIlroy had no illusions about his ability to lead men. Or rather, he did have one illusion he thought that he was completely unfit as a leader. It was true that his strictest orders were disobeyed with cheerful contempt, but it was also true his mildest requests were Everyone in the survey except McIlroy realized this, and even he accepted this without thinking about it. He had fallen into the habit of suggesting mildly anything that he wanted done, and writing orders he didn't particularly care to have obeyed. For example, because of an order of his stating that there would be no assured of a constant supply of home-made, but passably good liquor. Even McIlroy enjoyed the surreptitious drinking. "I'll certainly be glad to get them off my hands," McIlroy said. "I hope they're in good order." "There doesn't seem to be any profit," Mr. Phelps said. "Claim?" a collector's bag. "A few mineral specimens would give us something to think about, man. across." All of these needed water to form, and their existence on the Moon puzzled him for a while. Then he opened the bag that had contained the Nickel Jones was the captain of a supply rocket. He made trips from and "I swear, Mac," said Jones, "another season like this, and I'm going drinks from a bottle of Scotch that Jones had brought him. "Oh, the money I like, but I will say that I'd have more if I didn't have to fight the union and the Lunar Trade Commission." McIlroy had heard all of this before. "How's that?" he asked politely. "You may think it's myself running the ship," Jones started on his tirade, "but it's not. The union it is that says who I can hire. The union it is that says how much I must pay, and how large a crew I need. And then the Commission ..." The word seemed to give Jones an unpleasant taste in his mouth, which he hurriedly rinsed with a sip of Scotch. "The Commission," he continued, making the word sound like an obscenity, "it is that tells me how much I can charge for freight." McIlroy noticed that his friend's glass was empty, and he quietly filled it again. "And then," continued Jones, "if I buy a cargo up here, the Commission it is that says what I'll sell it for. If I had my way, I'd charge only fifty cents a pound for freight instead of the dollar forty that the profit I could make by cutting rates the other way." "Why not?" asked McIlroy. He knew the answer, but he liked to listen to "Near cost it is now at a dollar forty. But what sense is there in charging the same rate to go either way when it takes about a seventh of the fuel to get from here to Earth as it does to get from there to here?" "What good would it do to charge fifty cents a pound?" asked McIlroy. they need these things on Earth, but they can't get them as long as it isn't worth the carrying of them. And then, of course, there's the water we haven't got. We could afford to bring more water for more people, and set up more distilling plants if we had the money from the nickel. "Even though I say it who shouldn't, two-eighty a quart is too much to pay for water." Both men fell silent for a while. Then Jones spoke again: "Have you seen our friend Evans lately? The price of chromium has gone profit." half. Can't you get in touch with him by radio?" "He isn't carrying one. Most of the prospectors don't. They claim that a radio that won't carry beyond the horizon isn't any good, and one that will bounce messages from Earth takes up too much room." " [Health, McIlroy, man.] " his suit was reading dangerously near empty. He turned back to his tractor, moving as slowly as he felt safe in doing. Running would use up efficient as the one in the tractor it wasted oxygen. By using the suit so much, Evans had already shortened his life by several days. He resolved not to leave the tractor again, and reluctantly abandoned his would be pretty bad if they clogged up some night." "Pressure's ten and a half pounds," said Cade. "Twenty pounds," Cade answered after a couple of minutes. "Take her up to ... no, wait, it's still leaking," Cowalczk said. "Hold "Good," said Cowalczk, "take the pressure up all the way, and we'll see what happens." "Eight hundred pounds," Cade said, after a short wait. "Good enough," Cowalczk said. "Tell that engineer to hold up a while, he can fix this thing as soon as he gets parts. Come on, Lehman, let's get out of here." "Two thousand?" Cade asked. "We only had seven hundred gallons reserve. How come we can operate now?" "We picked up twelve hundred from the town sewage plant. What with using the solar furnace as a radiator, we can make do." "Oh, God, I suppose this means water rationing again." "You're probably right, at least until the next rocket lands in a couple of weeks." carrying several days reserve of oxygen and supplies. Director McIlroy has expressed a hope that Evans will be found before his oxygen runs out. dark. Little hope is held for radio contact with the missing man as it is believed he was carrying only short-range, intercommunications equipment. Nevertheless, receivers are ... "Well, yes," Jones answered. "I thought that it might happen that a rocket would be needed in the search."

<question>:
Why is Jones a change in the pricing structure for supply runs?

<options>:
A He thinks it would save time in writing contracts
B He thinks he can make a bigger profit if he has more control
C It would allow more necessary supplies to reach Earth
D He wants to be able to carry more expensive supplies

<answer>:

C