Javier Is Walking Through His Yard in Deep Twilight

Multiple Choice

Javier is walking through his yard in deep twilight.Which of the following statements most accurately describes the visual system or systems he is using?

A) He is relying on the photopic system, which is associated with the cones, because cones are sensitive to color.
B) He is relying on the scotopic system, which is associated with the rods, because rods are more sensitive to light than cones are.
C) He is relying on the Purkinje shift to adjust to the decreasing levels of light available to his eyes.
D) He is relying on both the photopic and scotopic systems because it is a time of intermediate light intensity.