Question 41: As well as ……in an office he used to have a part-time as a waiter.

After “as well as” we often use a V-ing verb (as well as ~ not only …but also)

Eg: She is a talented musician as well as being a photographer. (She is both a talented musician and a photographer.)

=> Answer B (Not only does he work at the office, but he used to work as an overtime waiter.)