Many college graduates are willing to start online shops to get over the period ________ they have difficulty finding a satisfactory job.

A．where

B．when

C．which

D．that

氯解磷定治疗有机磷酸酯中毒的主要机制是

A．与结合在胆碱酯酶上的磷酸基相作用而使酶复活

B．与胆碱酯酶结合，保护其不与有机磷酸酯类结合

C．与乙酰胆碱结合，阻止其过度作用

D．与胆碱能受体结合，使其不受磷酸酯类抑制

E．与游离的有机磷酸酯类结合，促进其排泄