单项选择题

Optimism is a ______ shown to be associated with good physical health, less depression and longer life.

A. trail
B. trait
C. trace
D. track
<上一题 目录 下一题>
热门 试题

单项选择题
It is very kind of you to do the washing-up, but you ______ it.
A. mustn't have done
B. shouldn't have done
C. oughtn't to have done
D. didn't have to do
单项选择题
I like ______ in the autumn when the weather is clear and bright.
A. this
B. that
C. it
D. one
相关试题