What is the full form of $JFM$?

$DDT$ residues are rapidly passed through the food chain causing biomagnification because $DDT$ is:

Given below are two statements.
Statement $I$ - Algal blooms impart a distinct color to the water bodies.
Statement $II$ - Some bloom-forming algae are extremely toxic to fishes but not to human beings and other animals.
In the light of the above statements,select the correct option:

The forest cover in India is approximately .....

$A$ large number of fish suddenly die in a lake near a village. Which of the following could be the reason for this?
$(a)$ Excessive use of urea and phosphate fertilizers in nearby fields.
$(b)$ Spraying of $DDT$ in the entire area.
$(c)$ The lake water has turned green and murky.
$(d)$ The population of phytoplankton in the lake has decreased,reducing the photosynthetic capacity.
Which two of the above reasons are responsible?

All statements regarding $BOD$ (Biochemical Oxygen Demand) are correct,except: