What is a straightforward description of a minus lens?

A minus lens is characterized by its ability to diverge light rays that pass through it, which can be conceptually understood by visualizing its structure in terms of prisms. When you consider the nature of a minus lens, it can indeed be depicted as resembling two prisms that are oriented apex to apex. This configuration illustrates how the lens causes parallel rays of light to diverge, acting much like two prisms coming together at their apex points.

In practice, this divergence is crucial for correcting nearsightedness (myopia), as it helps bring light rays into focus on the retina. Therefore, the description of the lens as two prisms meeting apex to apex accurately reflects both the optical function of the lens and its geometric properties.

The other options do not accurately represent the defining characteristics of a minus lens. For instance, two prisms base to base would create convergence rather than divergence, while a flat lens with enhanced curvature does not describe the optical behavior typical of a minus lens. Lastly, a lens with a uniform thickness does not capture the specific curvature changes present in minus lenses, which are typically thinner at the center than at the edges.