单选题 I would have come to see you had it been possible, but I ______ so busy then.
A. had been B. was C. were D. would be

【正确答案】 B
【答案解析】[解析] 这个句子是虚拟语气，前半句为假设，后半句为事实，所以用一般过去时，选B。