【名词&注释】
胆碱酯酶活力(cholinesterase activity)、全血胆碱酯酶(whole blood cholinesterase)、急性有机磷杀虫药中毒(acute organophosphorus pesticide poison ...)
[单选题]轻度急性有机磷杀虫药中毒时全血胆碱酯酶活力测定是( )
A. 100% B. 90%~70% C. 70%~50% D. 50%~30% E. <30%