Whom is Mark's retinal prosthesis ready for? A.For those who have been blind from birth. B.For those who still have faint vision. C.For the blind who once had eyesight. D.For those who still have one healthy eyE.
A.For B. B.For C. C.For D. D.For
【参考答案】
C 解析：答案的依据在第五段的第一句：The retinal prosthesis and other devi......