题干
It is a strange phenomenon that some young people today think it is their parents’responsibility to earn money and_______ to spend it.
A：them
B：they
C：their
D：their
答案(点此获取答案解析）
D
转动，线圈中产生的交流电动势e随时间t变化的情况，如图所示，下列说法中正确的（ ）
