The first book (which was) written for children came out last year.which was 省略了 第一本为儿童著的书去年发表了 你可以用排除法 A,主动形式,错,排除 C,last year与being时态不一致,排除 D,to be表示将来,与last year时态不一致,排除
B 意思是 为儿童著的第一本书去年发表了。 主语是the first book, 谓语是came out. 完整写这句话可以为 The first book (which was) written for children came out last year. which was 省略了 过去分词written作为定语修饰book