细菌性食物中毒的治疗原则除了

A．迅速排出毒物(催吐、洗胃)

B．对症治疗

C．治疗腹痛腹泻，纠正酸中毒

D．细菌性食物中毒的患者均可用抗生素

E．特殊治疗

Scientists are convinced_____the positive effect of laughter_____physical and mental health.     

A．of; at

B．by; in

C．of; on

D．on;at