He felt like a character in a story book which had gazed out for a moment in his brief, imagined life at the real world. A. that gazed out B. who did gaze out C. who had gazed out D. No improvement

The correct answer is C. who had gazed out.

The sentence is about a character in a story book who has gazed out for a moment in his brief, imagined life at the real world. The use of the past perfect tense (had gazed) indicates that this event happened

before the character’s brief, imagined life. The use of the relative pronoun who indicates that the character is a person.

The other options are incorrect because they do not accurately reflect the meaning of the sentence. Option A, that gazed out,

uses the relative pronoun that, which is used to refer to things, not people. Option B, who did gaze out, uses the simple past tense, which does not accurately reflect the fact that this event happened before the character’s brief, imagined life. Option D, No improvement, is incorrect because the sentence is grammatically incorrect without the use of the past perfect tense.