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."
In this sentence, the use of commas to separate the items may lead to confusion because there are additional phrases (e.g., "such as carrots") that also contain commas. Semicolons should be used to clearly separate the main items in a complex list.