Final answer:
Silently repeating a phone number to remember it is an example of rehearsal, a strategy that helps move information from short-term to long-term memory.
Step-by-step explanation:
The example of silently repeating a phone number to oneself best demonstrates the process of rehearsal, which is a memory-enhancing strategy. This conscious repetition of information aids in transferring it from short-term to long-term memory. The student is likely using both chunking, by organizing the number into manageable bits, and elaborative rehearsal, by possibly associating the number with additional information such as recognizing the area code as belonging to a certain location.