Answer:
a. maintenance rehearsal.
Explanation:
Maintenance rehearsal -
It refers to the method of continuous speaking or thinking of a particular piece of information is referred to as maintenance rehearsal .
The method is adapted to learn or memorize the information , quickly .
Since , the short term memory can keep the information for 20 second , which can be further increased by practice the information again and again  .
Hence, from the given scenario of the question,
The correct term is a. maintenance rehearsal .