The sentence that requires semicolons instead of commas is:
A well-balanced diet includes root vegetables, such as carrots, dark red fruits, such as strawberries, and whole grains, such as brown rice.
This sentence has multiple items in a list that contain internal commas, which can create confusion. To clarify, semicolons should be used to separate the main items:
"A well-balanced diet includes root vegetables (such as carrots); dark red fruits (such as strawberries); and whole grains (such as brown rice)."
If you are following a traditional formatting style for lists with internal punctuation, semicolons help avoid ambiguity.