Final answer:
Gerard's difficulty in recalling the song title was due to the tip-of-the-tongue phenomenon, a retrieval failure where information cannot be immediately produced until cued.
Step-by-step explanation:
The initial difficulty Gerard experienced was most likely caused by d) the tip-of-the-tongue phenomenon. This phenomenon occurs when a memory seems to be just out of reach, as if it's on the "tip of your tongue," but you can't quite retrieve it. Hearing the songwriter's name likely provided a cue that helped Gerard retrieve the song title from his long-term memory storage.
In cognitive psychology, the tip-of-the-tongue phenomenon is a common retrieval failure characterized by the sensation of knowing the information, yet being temporarily unable to produce it. It's not to be confused with proactive interference, where old information impedes the recall of newer information, or with retroactive interference, where new information hinders the recall of older information. The tip-of-the-tongue state can be momentary and is typically resolved by a trigger or cue, as in Gerard's case.