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

<passage>:
WORLD. IT DIDN'T EVEN HAVE A IN THE GARDEN they skipped several steps in the procedure. on the body? it required a fine adjustment. But they were disappointed that they found nothing for several hours as they hovered high over the rotation. Then it came—clearly and definitely, but from quite a small location only. "Limited," said Steiner, "as though within a pale. As though there were but one city, if that is its form. Shall we follow the rest of the surface to find another, or concentrate on this? It'll be twelve hours before it's back in our ken if we let it go now." had refused to read Positive when turned on the inventor himself, told the machine so heatedly. The machine replied, with such warmth that its relays chattered, that Glaser did not he had only ordinary , the machine insisted. the acknowledged superior minds of the Earth. In space it had been a it had read Positive on a two-inch-long worm, only one of them out of So it was with mixed expectations that Steiner locked onto the area individual, though this could not be certain) and got very definite action. Eppel was busy. The machine had a touch of the ham in it, and assumed an air of importance when it ran these tests. of us will get some sleep. If you find no other spot then we will go down on that one the next time it is in position under us, in about twelve hours." "You don't want to visit any of the other areas first? Somewhere away from the thoughtful creature?" "No. The rest of the world may be dangerous. There must be a reason that thought is in one spot only. If we find no others then we will go down boldly and visit this." So they all, except Steiner, went off to their bunks then: Stark, the Captain Gregory Gilbert, the executive officer Dawn did not come to the moon-town. The Little Probe hovered stationary went down to visit whatever was there. "There's no town," said Steiner. "Not a building. Yet we're on the from?" "I don't know, but they're right in the middle of it. Land here. We'll go to meet them at once. Timidity has never been an efficacious tool with us." "I have only one tongue by the eagle, by the squirrel, by the ass, by the English." wouldn't have a drink on you for a tubful of thirsty travellers, would you?" "The fountain." "Ah—I see." But the crew all drank of the fountain to be sociable. It was water, but water that excelled, cool and with all its original bubbles like the first water ever made. "Are there any other people here?" Stark asked the man. "But are there any others?" "How would there be any others? What other kind of people could there The captain was a little puzzled by this, but he went on doggedly: "Ha-Adamah, what do you think that we are? Are we not people?" "And the damnest thing about it," muttered Langweilig, "is, how are you going to prove him wrong? But it does give you a small feeling." "Can we have something to eat?" asked the Captain. "Pick from the trees," said Ha-Adamah, "and then it may be that you will want to sleep on the grass. Being not of human nature (which does not need sleep or rest), it may be that you require respite. But you are free to enjoy the garden and its fruits." "We will," said Captain Stark. They wandered about the place, but they were uneasy. There were the animals. The lion and lioness were enough to make one cautious, though they offered no harm. The two bears had a puzzling look, as though they wanted either to frolic with you or to mangle you. "If there are only two people here," said Casper Craig, "then it may be that the rest of the world is not dangerous at all. It looked fertile wherever we scanned it, though not so fertile as this central bit. And "All things are possible." And it was then that Ha-Adamah, the shining man, gave a wild cry: "No, no. Do not approach it. It is not allowed to eat of that one!" It was the pomegranate tree, and he was warning Langweilig away from it. not the idea that it was the apple that was forbidden go back only to a exegesis, however, the pomegranate is usually indicated." "To die I do not understand. I am taught that it is a property of even death could come if this happiness were ever lost. I am taught "Yes, since I am the only man, and knowledge is natural to man. But I "No. It would be no contest. I would not like to humble you." They were there for three days. They were delighted with the place. It was a world with everything, and it seemed to have only two inhabitants. They went everywhere except into the big cave. "What is there, Adam?" asked Captain Stark. "The great serpent lives there. I would not disturb him. He has long been cranky because plans he had for us did not materialize. But we are taught that should ever evil come to us, which it cannot if we persevere, it will come by him." They learned no more of the real nature of the sphere in their time and that ours and all the others we have visited are fallen worlds. we have been seeking for centuries. It would be a crime if anyone "I too am convinced," said Steiner. "It is Paradise itself, where the lion lies down with the lamb, and where the serpent has not prevailed. It would be the darkest of crimes if we or others should play the part of the serpent, and intrude and spoil." "I am probably the most skeptical man in the world," said Casper Craig the tycoon, "but I do believe my eyes. I have been there and seen it. It is indeed an unspoiled Paradise Parties. Write, Gram, or call in person at any of our planetary offices as listed below. Ask for Brochure—Eden Acres Unlimited." Down in the great cave that Old Serpent, a two-legged one among whose names were "Snake-Oil Sam," spoke to his underlings: "It'll take them fourteen days to get back with the settlers. We'll have time to overhaul the blasters. We haven't had any well-equipped and slaughter and stow before there was another batch to take care of." "I think you'd better write me some new lines," said Adam. "I feel like a goof saying those same ones to each bunch." He looked proudly around at the great cave with its mountains and tiers space-sealed the rather large pile of bone-meal in one corner. "We will have to have another lion," said Eve. "Bowser is getting old, and Marie-Yvette abuses him and gnaws his toes. And we do have to have a big-maned lion to lie down with the lamb." "I know it, Eve. The lion is a very important prop. Maybe one of the "I'm working on it." Casper Craig was still dictating the gram: "Amazing quality of longevity seemingly inherent in the locale. Climate ideal. Daylight or half-light. All twenty-one hours from Planet Delphina and from Sol. Pure water for all industrial purposes. Scenic Briton. "Why in cosmos would we want an armed escort?" "It's as phony as a seven-credit note!" Theologically unsound, dramaturgically weak, philologically impossible, zoologically rigged, salted conspicuously with gold and shot through with anachronisms. And moreover he was afraid to play me at checkers." "What?" was just that he chose not to make our acquaintance personally." "But it was Paradise in one way," said Steiner at last. "All the time we were there the woman did not speak."

<question>:
Why was the cave the only place that was not visited?

<options>:
A The cave was only a reflective illusion from the bright light.
B The crew ran out of time but planned to examine it upon their next arrival
C Adam, or Ha-Adamah, told the crew that it was much to dangerous as there were evil creatures living inside.
D The serpent lives there and the crew was told that he was cranky.

<answer>:

D