单选题 He is such a ______ that he built a porch for his house last summer during his vacation.
A. productive B. versatile C. authoritative D. solitary

【正确答案】 B
【答案解析】productive生产性的，多产的；versatile多才多艺的，巧手的；authoritative权威的，官方的； solitary孤独的。