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

<passage>:
That's just line! Is Evans—?" Evans was carrying a block of ice into the tractor when he saw the The meteor, a pebble, a little larger than a match head, traveled through space and time since it came into being. The light from the star that died when the meteor was created fell on Earth before the first lungfish ventured from the sea. In its last instant, the meteor fell on the Moon. It was impeded by "Evans, man!" said Jones' voice in the intercom. "Alive you are!" Evans' tractor. It drilled a small, neat hole through the casing of the steam turbine, have been formed by steam some time, because there's a floor of ice in all of 'em. It was two days to sunrise, where Evans stood. Evans, who had no watch, thought of the time as a quarter after Evans was a prospector, and like all prospectors, a sort of jackknife "No," Evans answered, "a Welshman, nothing more." "You might let me have some food," Evans continued. "I'm getting short half, and he was lucky to break even. "Claim?" "Sure, man, I've thousands of tons of water here. It's the richest mine on the Moon!" THE END Evans was about three hundred miles east of Williamson Town, the site of the first landing on the Moon. Evans was due back at Williamson Town at about sunset, that is, in about sixteen days. When he saw the wrecked turbine, he knew that he wouldn't "Batteries must be dead," he told himself. "Why isn't the generator working, man?" he asked. Evans sealed the turbine from the rest of the steam system by closing Evans watched the lights flicker and go out, and he guessed what the the sun shone as brightly as though there were no sun. They might have appeared to waver slightly, if they were behind outflung corona flares. at all, but he thought in the strictest sense that it would be morning on the Moon for another week. nine banks of mirrors would not respond to the electric controls, and one bank moved so jerkily that it could not be focused, and it "What happened here?" Spotty Cade, one of the electrical technicians don't work." "Meteor shower," Cowalczk answered, "and that's not half of it. Walker says he's got a half dozen mirrors cracked or pitted, and Hoffman on bank three wants you to replace a servo motor. He says the bearing was "When did it happen?" Cade wanted to know. "That could hurt," Cowalczk admitted, "but there was only one of them." "You mean only one hit our gear," Lehman said. "How many missed?" Nobody answered. They could all see the Moon under their feet. Small craters overlapped and touched each other. There was—except in the places that men had obscured them with footprints—not a square foot that didn't contain a crater at least ten inches across, there was not a square inch without its half-inch crater. Nearly all of these had been made millions of years ago, but here and there, the rim of a crater covered part of a footprint, clear evidence that it was a recent one. After the sun rose, Evans returned to the lava cave that he had been crystals on the cave wall with his geologist's hammer, and put them into a collector's bag. "A few mineral specimens would give us something to think about, man. These crystals," he said, "look a little like zeolites, but that can't be, zeolites need water to form, and there's no water on the Moon." He chipped a number of other crystals loose and put them in bags. One of them he found in a dark crevice had a hexagonal shape that puzzled him. One at a time, back in the tractor, he took the crystals out of the bags and analyzed them as well as he could without using a flame which would waste oxygen. The ones that looked like zeolites were zeolites, all right, or something very much like it. One of the crystals that he thought was quartz turned out to be calcite, and one of the ones that he was sure could be nothing but calcite was actually potassium nitrate. "Well, now," he said, "it's probably the largest natural crystal of potassium nitrate that anyone has ever seen. Man, it's a full inch 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 unusual hexagonal crystals, and the puzzle resolved itself. There was nothing in the bag but a few drops of water. What he had taken to be a type of rock was ice, frozen in a niche that had never been warmed by the sun. on the opposite side. For a while Earth was a dark disk in a thin halo, and then the light came to be a crescent, and the line of dawn began to move around Earth. The continents drifted across the dark disk and into the crescent. The people on Earth saw the full moon set about the same time that the sun rose. Nickel Jones was the captain of a supply rocket. He made trips from and to the Moon about once a month, carrying supplies in and metal and ores out. At this time he was visiting with his old friend McIlroy. and not worth mining here the low-grade ores of uranium and vanadium, 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 "Have you seen our friend Evans lately? The price of chromium has gone " [Great Health, man.] The sun was halfway to the horizon, and Earth was a crescent in the sky when Evans had quarried all the ice that was available in the cave. The thought grew on him as he worked that this couldn't be the only such chipping, he could locate small bubbles up to an inch in diameter, each a bubble. Suddenly, Evans noticed that the gauge on the oxygen tank of so much, Evans had already shortened his life by several days. He dawning line of light covered half of Earth, and Earth turned beneath it. the sweat. It didn't help much, and it left a blurred spot in his vision. That annoyed him. "Scale stuck in the valve," Cowalczk answered. "Are the reactors off?" "Twenty pounds," Cade answered after a couple of minutes. "O.K.," said Cade. "An engineer here says there's no manual cutoff." "What did you do?" asked Cade. "The light went out and came on again." McIlroy released a statement today that Howard Evans, a prospector is missing and presumed lost. Evans, who was apparently exploring the Moon in search of minerals was due two days ago, but it was presumed that he was merely temporarily delayed. Evans began his exploration on August 25th, and was known to be McIlroy has expressed a hope that Evans will be found before his Search parties have started from Williamson Town, but telescopic search from Palomar and the new satellite observatory are hindered by the fact that Evans is lost on the part of the Moon which is now dark. Little hope is held for radio contact with the missing man as it is believed he was carrying only short-range, "Like as not, you're right," McIlroy replied, "but if I know Evans, he'd tells me that Evans will be found." "Well, yes," Jones answered. "I thought that it might happen that a rocket would be needed in the search." The light from Earth lighted the Moon as the Moon had never lighted Earth. The great blue globe of Earth, the only thing larger than the stars, wheeled silently in the sky. As it turned, the shadow of sunset crept across the face that could be seen from the Moon. From full Earth, neck was stiff from sleeping in such an awkward position. "About Evans?" Phelps shook his head slowly. "Palomar called in a few this banker, who had never met Evans, was losing so much sleep about

<question>:
Why does Evans have difficulty identifying crystals?

<options>:
A All of the crystals he found were very rare
B He does not have much experience in doing so
C They were not actually crystals to begin with
D None of the crystals were native to the moon

<answer>:

C