Steepening an RGP lens can be achieved by which of the following methods?

Steepening a rigid gas permeable (RGP) lens is achieved primarily by adjusting the base curve of the lens. When you steepen the base curve, you create a curvature that is more pronounced, which allows the lens to fit more closely to the shape of the cornea. This adjustment enhances the lens’s overall fitting characteristics, improving comfort and optical performance by ensuring better alignment with the eye's surface.

In contrast, decreasing the overall diameter typically affects the lens's edge profile and overall coverage on the cornea rather than the steepness of the curve. Flattening the base curve would lead to a less steep lens, which could result in a poorer fit. Changing the lens type does not inherently alter the steepness of an existing lens; it simply refers to switching to a different lens design, which may or may not have a different base curve profile. Thus, steepening the base curve is the direct method for achieving the desired steepness in an RGP lens fitting.