Oil slick causes mass scale death of fishes due to

Which of the following is normally not an atmospheric pollutant?

Given below are two statements:
Statement $I:$ In a scrubber,the exhaust from the thermal plant is passed through a spray of water or lime to remove gases like $SO_2$.
Statement $II:$ Particulate matter $(PM\,2.5)$ cannot be removed by a scrubber but can be removed by an electrostatic precipitator.
In the light of the above statements,choose the most appropriate answer from the options given below:

Biochemical Oxygen Demand $(BOD)$ is a measure of:

Thermal pollution is more prevalent near

Black foot disease is caused by the toxicity of which of the following?