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

<passage>:
the U.S. copyright on this publication was renewed.] I The girl with the Slider egg glittering in her hair watched the the charge of grand theft by secreting a fresh Slider egg in his to be a muck man, Jumpy. I'm going out to Jordan's Planet and hunt Slider eggs." he had been working on a method of keeping Slider eggs alive. The potential changelings must be fully informed of the rights and hazards of altered shape before they signed a release. The requirement held senescence could be staved off, however, any man could have bulging biceps and a pencil waist, if he could pay for the treatment. was even a short fad of deliberate deformities, with horns at the techniques were perfected to adapt humans to the dozen barely habitable controls than he could inside a pressure suit. On more bizarre planets a few light-years away the advantages of changeling bodies were greater. to spend in rehabilitation. "What types of changelings do you have orders for right now, doctor?" with the arm structure modified into pseudo-wings or gliding. Then we Asa raised his eyebrows. "Why such a difference? Everyone knows about muck men living in the mud while they hunt Slider eggs. But don't your conversions make the changeling comfortable in his new environment?" "Sure they do," said the doctor. "We can make you think mud feels better than chinchilla fur and we can have you jumping like a grasshopper despite the double gravity. But we can't make you like the sight of yourself. And we can't guarantee that a Slider won't kill you." important, his companion had done time on Jordan's Planet before and had wanted to return. "It's the Slider eggs," explained Kershaw, the two-time loser. "The ones you see on Earth knock your eyes out, but they've already begun to die. There's nothing like a fresh one. And I'm not the first to flashes maybe four times a day. So I stole a new one and got caught." Asa had held a Slider egg in his hand as he gazed into it. He could understand. The shell was clear as crystal, taut but elastic, while the albumen was just as clear around the sparkling network of organic filaments that served as a yolk. Along these interior threads played tiny flashes of lightning, part of some unexplained process of life. Electrical instruments picked up static discharges from the egg, but Hardly anyone faced with the beauty of a Slider's egg bothered to random, fitful gleamings, and then there would be a wild coruscation of light, dancing from one filament to the next in a frenzy of brilliance. It took about four years for a Slider egg to die. Beauty, rarity and ever seen. If Asa had found a means of keeping them alive it would have made him wealthy at the expense of the Hazeltyne monopoly. "You know what I think?" Kershaw asked. "I think those flashes are the egg calling its momma. They sparkle like a million diamonds when you scoop one out of the muck, and right away a Slider always comes swooping out of nowhere at you." Sliders?" When the Slider catches you, you leap up while it buries its jaws in Everyone had seen pictures of muck men. It was different having one stand beside you. Kershaw looked much like an enormous frog except that his head was still mostly human. He was sitting on webbed feet, his lower legs bent double under huge thighs, and his trunk tilted forward as an ordinary man's legs. The hands had become efficient scoops, with broad fingers webbed to the first joint and tipped with spade-like claws. The skin was still pinkish but had become scaly. Not a thread of hair showed anywhere on the body, not even on the head. This, Asa realized, was what he looked like himself. It would have been more bearable if the head had not retained strong traces of humanity. The nostrils flared wide and the jaws hardly emerged from the neck, but the ears were human ears and the eyes, under as Kershaw's head. a gun and a long knife. "Names?" he growled. He was a foot taller than Graybar and big everywhere in proportion. "Everything that grows on this planet is poison. So if you got any ideas of hiding out till your term is up, forget 'em. Right here is where you eat." mud, if not precisely as pleasant to the touch as chinchilla fur, was not at all uncomfortable, and the dripping air caressed their skins like a summer breeze back on Earth. Tiny, slippery creatures skidded "Keep your eyes open," Kershaw said. "There's a Slider been around here Sliders, but this meant little, for the beasts lived under the mud as Kershaw halted again when they came to a roughly circular area some ten dug in gradually widening semi-circles opposite each other. They had watch. "A big one," Kershaw said. He held it, still smeared with traces of at it." A SLIDER EGG The egg was flashing with a mad radiance, like a thousand diamonds for help. Asa looked around. "Jump!" he shouted. At the edge of the clearing a segmented length of greenish black scales, some two feet thick and six feet high, had reared up out of the weeds. The top segment was almost all mouth, already opened to show row upon row of teeth. Before Asa could draw his gun the Slider lowered down from where it was hinged over his head. As he landed he turned "We've got an egg but a Slider wants it back." the Slider's first rush, for he was trying to hop on one leg as if the Kershaw had dropped it. The Slider, eight flippers on each side working flesh. The Slider writhed, coating its wound in mud, and twisted toward the Slider turn toward the patch of weeds where he would land. His legs Slider would be on top of him before he could escape. As he landed he at the dead Slider and shook his head. "Tell me, what are the odds on eggs brought out. Of course you're not supposed to stand there admiring the eggs like I did while a Slider comes up on you." Asa hopped over to the egg, which was still full of a dancing radiance the egg. "Just in case there are any more Sliders around," he explained. "Makes no difference," said Kershaw, pointing upward. "Here comes the The big machine circled them, hovered to inspect the dead Slider, and settled down on broad skids. Through the transparent nose Asa could see "I see you took care of the Slider," he said. "Hand over the egg." approximately by the body of the dead Slider. Dorr could return for the If he tried to carry the egg back, Asa knew, Sliders would attack him which he and Kershaw had certainly deviated on their outward trip. What was the night like on Jordan's Planet? Maybe Sliders slept at this strange new body, and if the Sliders left him alone.... carcass of the dead Slider and took shelter behind it. hover, thumped down upon the mud and slid forward. As Asa jumped aside, the landing skids caught against the Slider's body and the helicopter From the way my face feels I ought to be getting a black eye pretty soon." "What happened?" who talked back to him should try arguing with the Sliders." She looked up at the machine-gun on the helicopter. "They feed at night, you know. And they eat their own kind," she said. "The Slider you killed would draw them like ants to jam." Asa glanced around quickly to make sure no Sliders had already come. He "We fight off the Sliders, then," she said, as matter of factly as if "Nope. In this drizzle, at night, the Sliders would be on us before

<question>:
What unique physical features do Sliders have flanking their bodies?

<options>:
A Massive jaws for consuming prey.
B A wormlike torso for smooth navigation.
C Sixteen flippers for gripping mud.
D Greenish black scales for camouflage.

<answer>:

C