Which option is considered poor in Photopic vision?

In photopic vision, which occurs under well-lit conditions, sensitivity generally refers to the ability to detect light stimuli. Under bright lighting, the photopic system is dominated by cones, which are responsible for high acuity and color perception but are less sensitive to low levels of illumination compared to rods, which operate better in dim light.

The correct option highlights that sensitivity is not as effective during photopic vision. While cones provide excellent visual acuity and color discrimination, they don't respond to low light levels, making them less sensitive than rods. Therefore, when it comes to detecting low levels of brightness in bright conditions, sensitivity is considered poor.

On the other hand, color vision and visual acuity are aspects that excel under photopic conditions due to the function of cone cells. Facial recognition also benefits from good visual acuity and color processing, allowing for more detailed image processing. These functions are not diminished in photopic conditions, which further highlights why sensitivity is the appropriate choice in this context.