---for college,a student must take an entrance test

To be considered for college,a student must take an entrance test.
选择A.意思是：为了申请学校,学生务必参加大学入学考试.
To be considered for 是申请的意思.
之所以用被动语态,因为对于句子主语学生来讲,是被考虑给入学机会,被考察是否符合要求.
to引导的不定时表示目的.