【题目】It's standard practice for a company like this one______ a security officer.
A.employed
B.being employed
C.to employ
D.employs

【答案】C
【解析】句意：像这样的一家公司，雇佣安保人员是一个标准惯例。It为形式主语，真正的主语是动词不定式to employ a security officer。故选C。