单选题 For nearly 50 years, Spook has been a ______ author writing 13' books including an autobiography and numerous magazine articles.

【正确答案】 D
【答案解析】prolific多产的,此处表示他是个多产的作家,是正确答案。prevalent普遍的,流行的;precautious警戒的,小心的;prospective预期的,有希望的。