Final answer:
The personal pronoun 'he' replaces the name 'Walt Disney' in the given sentence because Walt Disney was a man.
Step-by-step explanation:
The personal pronoun that replaces the phrase "(Walt Disney)" in the sentence is: "He may be best known for creating Mickey Mouse." In this sentence, the pronoun "He" replaces the proper noun "Walt Disney." Pronouns are used to avoid redundancy and repetition in writing, providing a smoother flow to the text. Using the pronoun "He" helps maintain clarity while avoiding unnecessary repetition of the person's name. This is a common and effective way to incorporate pronouns in writing, especially when referring back to a previously mentioned noun.