Select the most appropriate option to fill in the blank.
The teacher assured: “You have completed your homework, __________?”

Correct option is C

The most appropriate option to fill in the blank is "haven’t you" to make the sentence grammatically and contextually correct.
· "Haven’t you" is used in a tag question format to confirm that the listener has indeed completed their homework.
· As per the context, the phrase "haven’t you" fits in very well and hence, it is the correct option.
· Tag questions are used for confirmation and usually follow the pattern of using the auxiliary verb from the statement in the opposite form (positive or negative).
· The statement "You have completed your homework" is positive, so the tag question should be negative: "haven’t you?"
· Correct sentence: The teacher assured: “You have completed your homework, haven’t you?”