Which of the following is found in the approaches to Kingston Harbor, between Simcoe Island and Amherst Island?

The area between Simcoe Island and Amherst Island, known for its navigational landmarks, indeed features Melville Shoal. Melville Shoal is a prominent underwater feature that can impact navigation, as it is located within the approaches to Kingston Harbor. Mariners should be aware of this shoal to avoid grounding their vessels when traveling through this route. Its presence emphasizes the importance of navigation charts and local knowledge when navigating the waters surrounding Kingston Harbor.

In contrast, the Upper Gap and the Boat Channel are navigational routes or passages, while Snake Island Bank is a different underwater feature not specifically located between those two islands. These distinctions help clarify why Melville Shoal is the correct answer in this context.