单选题
He intends to______the secretary he has dismissed by a less glamorous but more efficient one.
【正确答案】
B
【答案解析】解析：replace vt．(用……)替换，(用……)取代；把……放回原处。substitute v.用……代替；代替，取代(句型：A substitutes[for]B甲代替乙；to substitute A for B用甲代替乙)。alter vt．改变，变更。alternate(with)vi．交替，更迭。