Final answer:
Tim was using suppression, which is the conscious effort to avoid thinking about distressing memories, in order to forget his embarrassment at the party.
Step-by-step explanation:
Every time Tim remembered how embarrassed he had been at the party, he immediately thought of something else to try to forget all about the party.
The technique Tim was using for the purpose of motivated forgetting is suppression.
Suppression involves consciously trying to forget or not think about painful or unwanted thoughts.
Repression, on the other hand, is an unconscious process by which anxiety-causing memories are blocked from consciousness, similar to how one might turn up the radio to avoid hearing the strange noise from their car and subsequently forget about it.
Retrograde amnesia and proactive amnesia involve the inability to recall past events or old information hindering the recall of newly learned information, respectively, and are not acts of motivated forgetting.