Where was the $UN$ Climate Change Conference held in $2012$?

Assertion: Eutrophication shows an increase in productivity in water.
Reason: With increasing eutrophication,the diversity of the phytoplankton increases.

In an ecological crisis,whose interference plays an important role?

Which of the following is a pollution-related disease?

Identify the odd one out regarding the process of bio-magnification.

Jhum cultivation is prevalent in $.................$.