单选题 If banks ______ the number of credit cards, the economy would improve.

A、 (A) limiting
B、 (B) limited
C、 (C) had limited
D、 (D) are limiting

【正确答案】 B

【答案解析】Limited is the correct if-clause verb for the second conditional. Choice (A) is the present participle. Choice (C) is the third conditional. Choice (D) is the present continuous.