OG详解-OG7 文法 Q29

Choice A is the best answer. The sentence indicates the title of a novel that won a Nebula Award, noting that Babel-17 by Samuel Delany won the award in 1967. 
Choice B is incorrect because the sentence identifies the year that Samuel Delany published a science fiction novel; it doesn’t indicate the novel’s title or that it won a Nebula Award. Choice C is incorrect because the sentence provides an introduction of Samuel Delany; it doesn’t indicate the title of a novel that has won a Nebula Award. Choice D is incorrect because the sentence indicates that one of Samuel Delany’s novels met the qualification for a Nebula Award; it doesn’t indicate the novel’s title or that it won an award.