Update Chapter 4 "End-of-chapter quiz"

[CorbanPendrak]

Description

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This pull request fixes several typos in the Chapter 4 End-of-chapter quiz without altering the structure or logic in the page.

Changes

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• Remove repeated affirmations from explanations
• Added some explanations
• Clarifies some questions
• Added some code marks

Purpose

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Because the explanations automatically appear with "Correct!" or "Incorrect." before the explanation, explanations that begin with affirmations such as "Correct", "That's right", and "Right", have been removed to reduce repetition. This pull request adds some explanations when the previous explanation only said whether the answer was correct. Some questions have been slightly modified for clarification. Some code marks, the ` that marks code, have been added.