Photosynthesis ceases when leaves wilt, mainly because

A) the chlorophyll in wilting leaves is degraded.
B) flaccid mesophyll cells are incapable of photosynthesis.
C) stomata close, preventing CO₂ from entering the leaf.
D) photolysis, the water-splitting step of photosynthesis, cannot occur when there is a water deficiency.
E) accumulation of CO₂ in the leaf inhibits enzymes.