不挂科搜题免费

问题:

[A]counterparts[B]substitutes[C]colleagues[D]suppo

答案:

[解析]上文指出,In a study, researchers sprayed oxytocin into the noses of half the subjects,可推知本句再讲与另外一组受试者比较。故选项A.counterparts相对物,相对应的人为正确答案。