When You Enter a Darkened Theatre, It Takes a While

Multiple Choice

 When you enter a darkened theatre, it takes a while before you can see your surroundings clearly. The most likely explanation for this phenomenon is that

A) the lens needs time to accommodate to the change in lighting.
B) the glutamate in rods has been depleted and more must be synthesized.
C) the visual system switches slowly between processing inputs from cones to inputs from rods.
D) it takes about 30 minutes for rhodopsin to regenerate after it has broken apart in response to light.