Fill in the blank with the most appropriate word.
What time ________ you go to bed?
A verb is used to express an occurrence, action, or state. It is the grammatical centre of the predicate in a sentence.
An auxiliary verb is a verb which gives is used in the formation of tenses, moods, tones, etc.
Option A is correct as the subject is you and the question talks about a routine.
The other options are wrong as the question talks about a routine. Therefore, have cannot be used. Also, does and is cannot be used as the subject is you.
The correct answer is A)do