After hearing a friend's telephone number for the first time, harold was immediately able to recite all seven digits of the phone number in perfect order. harold most likely used his to recite these digits.

Short-term memory, which hold but rarely analyzes/manipulates small bits of information that is readily accessible to your brain for a short time.

Harold used his short term memory to recite the digits.

Explanation:

Short-term memory (STM) describes an individual's ability or capacity to store information in the mind for a short period of time. Such information can be readily made available within the short period which it exists in the mind.

When Harold's friend gave him a telephone number for the first time, Harold quickly stored the information (7 digit number) in his short term memory and was able to quickly make the numbers available (remember them) because they were still active in his short-term memory for that short period of time.

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