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

药物变态反应的全身性反应包括

A．神经系统变化和呼吸道反应

B．红斑狼疮样反应

C．血液病样反应、血清病样反应

D．心血管系统反应

E．肝炎样反应、肾脏损害