The environment is only regarded as a pristine collection of plants and animals.

Which of the following is not a natural resource?

List two main causes of the pollution of water of the river Ganga. State how pollution and contamination of river water prove harmful for the health of the people of neighbouring areas.

$(a)$ Mention any two advantages of constructing dams.
$(b)$ Name a dam which was a subject of much opposition from locals as well as $NGOs$.
$(c)$ Mention any three problems which may arise due to the construction of large dams.

The most rapidly dwindling natural resource in the world is

Name the group of bacteria whose presence confirms the contamination of river water.