Trey's strategy is an example of meta-memory.
Explanation:
Meta-memory is a strategy that involves in self-monitoring of memory power. Meta-memory generally refers to knowledge and awareness of our own memory processes.
Meta-memory strategy will be commonly followed by students for memorizing their answers. They usually follow some tricks, clue words or cues to memorize the answers strongly.
In the above scenario, Trey follows meta-memory strategy to memorize the planets name for his science exam. He uses mnemonic technique to remember the planets name.
