Question

which physiological change in the eyes of the older adult causes difficulty in adaption when going from light to dark rooms?
slower opening and closing of the pupils
degradation of the rod cells
opacity of the lens
increased intraocular pressure

Explanation:

Rod cells are responsible for vision in low - light conditions. As older adults age, the degradation of rod cells impairs the eye's ability to adapt from light to dark environments. Slower pupil movement affects light entry but not as directly as rod - cell degradation. Lens opacity impacts overall vision clarity, not specifically dark - adaptation. Increased intraocular pressure is related to glaucoma and not to dark - adaptation.

Answer:

Degradation of the rod cells