The correct choice is: a. A
In a refracting medium, when light passes from a rarer medium to a denser medium (e.g., from air to water), the refracted rays diverge. Diagram A likely represents this scenario as the other diagrams (B, C, and D) show converging rays.
Diagram A likely represents refracted rays diverging. When light travels from a rarer medium (like air) to a denser medium (like water), refraction occurs. In this case, the angle of incidence is greater than the angle of refraction, causing the refracted rays to spread out or diverge. This phenomenon is a result of the change in the speed of light as it moves from one medium to another. The bending of light is governed by Snell's Law, and the degree of divergence depends on the refractive indices of the two media involved. Diverging rays are characterized by a spreading apart as they pass through the refracting medium. Diagrams B, C, and D likely depict situations where light is converging due to the opposite scenario, where it transitions from a denser medium to a rarer medium.