Question

Now most families have only one child _____ our country’s one-child policy.
A.  since        B. because           C. because of

Answer 1

C

試題分析：since由于，自從……以來；because因?yàn)�；because of因?yàn)�。句意：因�(yàn)槲覈?guó)的一孩政策，現(xiàn)在許多家庭只有一個(gè)孩子。Because和because of都表示原因，區(qū)別是前者接從句，后者接名詞性短語。下文our country’s one-child policy為名詞性短語，故選C.