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 that contain commas, so semicolons are necessary to clearly separate the different categories. The revised sentence with semicolons would look like this:
"A well-balanced diet includes root vegetables, such as carrots; dark red fruits, such as strawberries; and whole grains, such as brown rice."