To be an astronaut, you must not only be strong in mind, but also be sound mentally and .
A. eventually
B. willingly
C. potentially
D. physically
网友回答
A. eventually
B. willingly
C. potentially
(答案→)D. physically
解析：词义辨析. A.最后;终于 B.欣然的 C.可能的 D.身体上的.句意:要成为一名宇航员,你不仅要有强大的智力,还要在身体上和心理上都要健康.故选D.