What is the meaning of the word "peak"?

The meaning of the word "peak" primarily refers to the highest point of something, often a mountain. In this context, "peak" embodies both the notion of a summit and the action of reaching that highest point. This interpretation aligns well with various usages of the term, such as in phrases like "the peak of the mountain" or "to peak in performance."

While "summit" specifically denotes the top of a hill or mountain, the action of "to reach the highest point" reflects achieving one's maximum degree of something, providing a broader understanding of the term across different contexts. This makes the second choice the most accurate representation of the word "peak."