Which sentence correctly uses an infinitive to express purpose? A. The regulation aims at reducing risks in banking B. To ensure compliance, banks developed new protocols C. Training programs help employees understanding the rules D. The committee decided reviewing the policy 答案解析 核心考点：动词不定式表目的。正确答案B使用'To ensure'开头的目的状语。A选项用'aims at'接动名词，C选项误用understanding，D选项缺少to。易错点：区分不定式作目的状语与其他动词形式。 正确答案：B