# The most important reason for decrease in biodiversity is :-

$\begin{array}{1 1}(a)\;\text{Habitat pollution}\\(b)\;\text{Indroduction of exotic species}\\(c)\;\text{Over-exploitation}\\(d)\;\text{Habitat destruction}\end{array}$

The most important reason for decrease in biodiversity is habitat destruction.
Hence (d) is the correct answer.