Final answer:
The sense of sight is best suited to detect a rash, as it allows for the observation of skin changes that touch alone cannot distinguish, while other senses like smell, hearing, and taste are not significantly involved.
Step-by-step explanation:
The best sense to detect a rash would be sight. The five senses are hearing, sight, taste, touch, and smell, which are all critical to interacting with the world around us. When it comes to detecting a rash, the sense of sight allows us to observe changes in skin color, texture, and appearance.
Conversely, touch can also provide information about the presence of a rash through the feeling of pain, pressure, or temperature changes in the skin. However, a visible inspection is usually the primary means of identifying a rash. While you could physically feel a rash through touch if it is raised or textured, sight gives us the ability to notice the affected area's details such as size, shape, color, and pattern that touch alone cannot provide. Importantly, other senses like smell, taste, or hearing do not have a significant role in the detection of a rash.