9.C最佳 分析:该题考查语序。该句的主语中心词为Students,其后的brave enough和to take this
adventure course为并列的形容词短语和不定式短语做后置定语。enough可作名词,形容词和副词用。enough作形容词修饰名词置于名词前后均可,但它作副词修饰形容词和副词时,只能置于这些词之后,故答案为C。又如:I felt that I was
not strong enough to travel. He didn't work hard enough and so he failed the
exam.