Stagnant water is the correct answer because mosquitoes and other insects require a specific environment to breed, and stagnant water provides the ideal conditions for them to reproduce. Here is a detailed explanation:

Why mosquitoes and other insects breed in stagnant water?
- Stagnant water refers to water that does not flow or move, such as in puddles, stagnant ponds, or water containers that are not regularly emptied or changed.
- Mosquitoes and other insects prefer stagnant water because it provides them with the necessary conditions for breeding and laying eggs.
- Stagnant water is usually rich in organic matter, such as decaying leaves or other debris, which serves as a food source for mosquito larvae and other insect larvae.
- These insects also require water that is relatively calm and undisturbed to lay their eggs. Flowing water or turbulent water would wash away the eggs, preventing them from developing.
- Stagnant water also tends to have a higher temperature compared to flowing water, which accelerates the development of mosquito larvae and other insect larvae.

Why do mosquitoes and other insects breed profusely in stagnant water?
- Mosquitoes and other insects have adapted to utilize stagnant water as an ideal breeding ground, allowing them to reproduce rapidly.
- Female mosquitoes lay their eggs on the surface of stagnant water or in areas that are prone to flooding. They can lay hundreds of eggs at a time, and these eggs hatch into larvae within a few days.
- Mosquito larvae, commonly known as wigglers, live in the water and feed on organic matter. They go through several stages of development before transforming into pupae.
- After a few days, adult mosquitoes emerge from the pupae and fly away, ready to reproduce and start the cycle again.
- Similarly, other insects like gnats, flies, and certain types of beetles also utilize stagnant water for their breeding purposes.

Preventing mosquito breeding in stagnant water:
- Stagnant water is a breeding ground for mosquitoes and other insects, so it is important to eliminate or treat any stagnant water sources to prevent their proliferation.
- Regularly empty and clean water containers such as buckets, flower pots, or bird baths to remove stagnant water.
- Keep gutters clean and free of debris to prevent water from accumulating.
- Avoid overwatering plants or allowing water to accumulate in low-lying areas of your yard.
- Use mosquito dunks or larvicides in stagnant water sources that cannot be eliminated, such as ponds or ditches, to kill mosquito larvae and prevent them from developing into adults.

In conclusion, stagnant water provides mosquitoes and other insects with the necessary environment for breeding and laying eggs. Understanding their breeding habits and taking preventive measures can help control their population and reduce the risk of mosquito-borne diseases.