ㄧ個句子 - 英檢

請問有人可以解釋一下以下""裡的句子的結構嗎?

我看了老半天不知道怎麼分析...謝謝

Because of the extent to which a college degree is accepted by employers
as proof of competence in a given field, college graduates are not only
more likely to receive more job offers...

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"Because of the extent to which a college degree is accepted by employers
as proof of competence in a given field"

謝謝


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