— Why does she look so tired?

— She ____homework all the morning and she still hasn't finished it. [ ]

A. is doing

B. has done

C. has been doing

D. was doing

对于放置子宫托，说法错误的是

A．子宫托大小因人而异
B．在每日晨起时放入，晚间取出，清洁备用
C．子宫托使用安全，可长期佩带不取
D．放置子宫托后应定期复查
E．子宫托放置不合适，可导致尿瘘或粪瘘