Final answer:
A plant lacking water with low turgor pressure is flaccid, leading to the stomata closing to conserve water.
Step-by-step explanation:
When a plant lacks water and has very little turgor pressure, it is referred to as being flaccid. In this condition, the stomata respond by closing. This is a conservation strategy to prevent further water loss through transpiration. Unlike what is suggested in choice c of the reference information, stomata generally close under drought conditions to conserve water, even though this can limit the plant's ability to photosynthesize because it reduces the intake of carbon dioxide.
The process involves the plant's guard cells, which flank the stomata and regulate their opening and closing through osmotic changes. When the plant experiences a lack of water, the guard cells lose water, become less turgid, and consequently, the stomatal pores close. This decreases water loss from the leaves and helps the plant survive periods of low water availability.