Answer: The cognitive technique Andrew has demonstrated is called "DEFERRED IMITATION". Option c is the most correct option.
Explanation: Deferred imitation is the process of doing what someone has done, after you watched the person for a long time. It is a way of mimicking someones behavior, because you have watched the person doing that many times.
Because Andrew watches the mothers vacuum always, as she clean the floor, Andrew has decided to act with his toy as he has been watching the mother do that, and he wants to imitate what he was been seeing.
An action can only be called deferred imitation, if such actions was as a result of an action that has been constant to our sight.