—What do you think people can do for their aged parents?

—They_________ do anything except to be with them and be themselves.

A．don’t have to

B．oughtn’t to

C．mustn’t

D．can’t

体格发育评价中，生长水平反映儿童（）

A.过去存在的问题

B.生长趋势

C.在某一年龄时点的体格发育达到的水平

D.个体差异

E.两项指标间的比例关系