Select the most appropriate option to fill in the blank.

My mother usually _______ for her classes at 9 a.m. and returns at 5 p.m

Leaves is the most natural and common way to express a habitual action in the present tense. It indicates a recurring event that happens at a specific time each day.

Has left would be appropriate if your mother had already left for her class today at 9 am, but it wouldn't be the best choice for describing a general habit.

Was leaving implies an action in progress in the past, which doesn't fit the context of a daily routine.

Is leaving could be used if you were talking about right this moment, but the context suggests this is a general routine that happens every day.

Therefore, Option A is the correct answer.