124. Found throughout Central and South America, sloths hang from trees by long rubbery limbs and sleep 15 hours a day, moving infrequently enough that two species of algae grow on its coat and between its toes. (A) sloths hang from trees by long rubbery limbs and sleep 15 hours a day, moving infrequently enough (B) sloths hang from trees by long rubbery limbs, they sleep 15 hours a day, and with such infrequent movements (C) sloths use their long rubbery limbs to hang from trees, sleep 15 hours a day, and move so infrequently (D) the sloth hangs from trees by its long rubbery limbs, sleeping 15 hours a day and moving so infrequently (E) the sloth hangs from trees by its long rubbery limbs, sleeps 15 hours a day, and it moves infrequently enough
这道题,为什么选择D我已经弄懂了,但是我反过来再看,觉得 既然D可以用 do, doing and doing 的结构,那么A中的 do and do,doing 这种结构正确吗?