China represents a huge opportunity to America, so it’s important for Americans to know _______ the Chinese work and think and to make strong friendships and connections with Chinese people.

A．why

B．what

C．that

D．how

青霉素V钾

A．火焰反应，火焰显紫色
B．供试品的吡啶溶液加铜吡啶试液1滴，即显紫色
C．供试品溶液加硝酸，即显红色，渐变为黄色
D．制备衍生物测其熔点，应为174～178℃
E．供试品溶液与三氯化铁试液作用，即显紫色
以下药物的鉴别反应为