We may recognize a face at a social gathering but be unable to remember how we know that person. this is an example of a. priming. b. the serial position effect. c. source amnesia. d. storage decay.

I believe the answer is: Source amnesia

Source amnesia refers The inability to remember when or where we learned a certain information, Despite having no problem in retaining and understanding that memory. The most common cause of source amnesia is the malfunction of Explicit memory.