Eutrophication includes all,except

$A$: Water hyacinth is one of the most invasive weeds.
$R$: It increases the dissolved oxygen of water.

Minamata disease is a pollution-related disease that results from:

What is the $BOD$ level of potable water?

High $BOD$ indicates $........$.

Given below are two statements:
Statement $I$: Electrostatic precipitator is most widely used in thermal power plants.
Statement $II$: Electrostatic precipitator in thermal power plants removes ionising radiations.
In the light of the above statements,choose the most appropriate answer from the options given below: