单项选择题

The "chronic reference doses" (in boldface in Paragraph 3) refer to ______.

A．the safe levels of pesticide exposure
B．the amount of fruits one can safely eat
C．one's digestive capacity for fruits
D．health values of fruits and vegetables

<上一题目录下一题>

热门试题

单项选择题From the conversation with the three white boys, we learn that Jimmy ______.

A．must have offended them before
B．was a pleasant boy to be talked to
C．was being humiliated for being black
D．must have got used to their behaviors

单项选择题By saying No doubt, we are all racist (in boldface in Paragraph 3) the author admits that ______.

A．we are all warlike by nature
B．we all discriminate against other peoples
C．we are all proud of our own race and nation
D．we all focus on the difference between races