有一种高效消毒剂的主要成分为三氯异氰尿酸(C₃O₃N₃Cl₃)，又称高氯精。有关高氯精的说法不正确是  [ ]

A．高氯精由C、O、N、Cl四种元素组成

B．高氯精分子中C、O、N、Cl原子物质的量之比为1∶1∶1∶1

C．高氯精中C、N两种元素的质量比为12∶14

D．高氯精中氯元素的质量分数为25％

A good friend from _____I was born showed up at my home right before I left for Beijing.

A．how

B．whom

C．when

D．which