State the environmental condition at which the rate of transpiration is the lowest. Suggest a reason for the low transpiration rate. Name an environmental condition which would be a suitable control for this investigation.

e)

(i)
condition: Low light intensity
reason: In low light conditions, the stomata on the leaves tend to close or open less widely. This reduces the surface area through which water vapor can diffuse out of the leaf, thereby decreasing the rate of transpiration.

(ii) A suitable control environmental condition would be normal laboratory conditions (or ambient room conditions). This provides a baseline for comparison, allowing researchers to observe the specific effects of varying light intensity, temperature, or humidity.