When       about one of the biggest problems today, many experts say that an energy crisis is approaching and is thus threatening mankind's survival．

A．asked

B．being asked

C．having asked

D．asking

下列哪种中药有固精缩尿、涩肠止泻的功效（）

A.浮小麦

B.山茱萸

C.金樱子

D.诃子

E.麻黄根