______ she couldn't understand was ______ more and more young people like to follow suit instead of keeping their own styles.

【正确答案】 A

【答案解析】第一个空格应填入一个主语从句引导词，且该词在从句中充当宾语，因此只能用what。第二个空格是一个表语从句引导词，because无此用法，排除。从句是一个完整的句子，因此不用what，答案为A。