My aunt treated me kindly _______ I were her own child.

My aunt treated me kindly _______ I were her own child.
A、as
B、though
C、as if
D、since
【正确答案】：C
【题目解析】：as 因为，由于；though虽然，尽管；as if犹如，好似；since自……以来；因为
句意：我姑妈待我很好，就好像我是她自己的孩子一样。