The structure that is thick to protect some of the reproductive structures in flowers is the sepal.
To clarify the options you provided:
- A: Style (the stalk that connects the stigma to the ovary)
- B: Answer (not a part of a flower)
- C: Petal (the colorful part that attracts pollinators)
- D: Power (not related to flower anatomy)
If you meant "sepal" instead of "style," then the sepal would be the correct answer, as it protects the flower bud and can sometimes also help protect the reproductive structures when the flower is in bloom.