Option 1 states that the aperture of a convex lens is equal to its radius of curvature. However, this is incorrect. The aperture of a lens refers to the diameter of the lens opening, and it is not directly related to the lens` curvature.

Option 2 suggests that the aperture of a convex lens is equal to its focal length. However, this is also incorrect. The focal length of a lens is the distance between the lens and its focal point, while the aperture represents the size of the lens opening.

Option 4 states that the aperture of a convex lens is equal to half of its focal length. This is incorrect as well. The aperture and the focal length are two distinct measurements and are not directly related to each other.

The correct answer is Option 3, which states that the aperture of a convex lens is independent of its radius of curvature. This means that the size of the lens opening (aperture) is not determined by the curvature of the lens. The aperture can be adjusted separately from the lens` curvature to control the amount of light entering the lens.