Which of the following is a true statement regarding color deficiency?

The statement that both normal and defective color vision can be trained is accurate because individuals can learn to compensate for color deficiencies through specific training and techniques. This can include using color-coded materials, learning to identify colors by context or brightness, and practicing with tools that enhance color differentiation. Training programs can be particularly beneficial for those with mild color deficiencies, helping them improve their ability to recognize and distinguish colors more effectively.

In contrast, the nature of the other statements varies: while color deficiency is often a chronic condition, it cannot be corrected through surgery since it relates to the absence or dysfunction of specific cone cells in the retina, not a problem that involves physical obstructions or malformations that could be surgical addressed. Additionally, color deficiency does not universally affect women more than men; in fact, it primarily affects men more frequently due to genetic factors, specifically the X-linked inheritance pattern of color vision deficiency. Thus, the idea that both normal and defective vision can be trained stands as the true statement in this context.