World Environment Day is celebrated on

Contribution of individuals: Women of Garhwal/Himachal.

$A$ 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?

Integrated organic farming has been adopted in India by

For which major rivers in India has the Ministry of Environment and Forests initiated action plans?

Which one of the following pairs is mismatched?