Concept:Aestivation is a summer dormancy state that helps animals survive hot, dry environmental conditions.
Explanation:Aestivation is a period of reduced activity or dormancy in animals.
Animals enter aestivation to escape extreme heat and water shortage.
Drought creates high temperatures and severe scarcity of water.
These harsh conditions force animals such as snails, lungfish, and earthworms to aestivate.
During aestivation, the animal's metabolic rate drops sharply to conserve energy and water.
The animal may also secrete a mucous coating or burrow underground to reduce water loss.
Wind alone does not produce the intense heat or dryness needed to trigger aestivation.
Rain brings cooler temperatures and more water, so it normally ends aestivation rather than causing it.
Cold temperatures trigger hibernation, which is winter dormancy, not aestivation.
Therefore, drought is the main condition responsible for aestivation.
Answer:B. Drought