In desert plants, stomata that are deep-seated or sunken to prevent transpiration are an example of what?

Correct answer: Morphological or anatomical adaptation

Answer: A. Sunken stomata are stomata positioned below the ordinary leaf surface, often in a small depression. This structural feature creates a more sheltered, humid layer of air near the pore and reduces the movement of dry air across it. As a result, diffusion of water vapour from the leaf can be reduced, helping a desert plant conserve water. Because the feature is a stable structural characteristic of the plant, it is a morphological or anatomical adaptation. B is wrong because the condition is not a temporary abnormality. C is wrong because it is not a disease. D is wrong because no chemical breakdown process is being described. The option uses “morphological or anatomical” because the feature concerns visible internal or external structure; it is not merely a physiological response. Memory cue: sunken stomata shelter the pore and save water.