He is about his chances of winning a gold medal in the Olympics next year.A. optimisticB.

问题补充：

He is about his chances of winning a gold medal in the Olympics next year.

A. optimistic

B. optional

C. optimal

D. obsessed

答案：

(答案→)A. optimistic

B. optional

C. optimal

D. obsessed

解析：句意：他对自己明年在奥运会上赢得金牌的机会很乐观。optimistic乐观的； optional可自由选择的，任意的；optimal 最佳的，最优的；obsessed迷住。根据句意判断选A。