Ruthless exploitation and pollution of the environment has increased the magnitude of waste materials,which has disturbed the operations of all important:

Which processes were included in the integrated organic farming by Ramesh Chandra Dagar,a farmer from Sonipat,Haryana?
$I-$ Bee-keeping
$II-$ Dairy management
$III-$ Water harvesting
$IV-$ Composting
$V-$ Chemical fertilizers
$VI-$ Chemical pesticides

Match the following columns:

Column-$I$	Column-$II$
$(a)$ Environment Act	$(1)$ $1974$
$(b)$ The Air Act	$(2)$ $1987$
$(c)$ The Water Act	$(3)$ $1986$
$(d)$ Amendment in The Air Act	$(4)$ $1981$

Ecosanitation is

Contribution of individuals: Women of Garhwal/Himachal.

$A$ lake near a village suffered heavy mortality of fishes within a few days. Consider the following reasons for this.
$A.$ Lots of urea and phosphate fertilizer were used in the crops in the vicinity.
$B.$ The area was sprayed with $DDT$ by an aircraft.
$C.$ The lake water turned green and stinky.
$D.$ Phytoplankton populations in the lake declined initially thereby greatly reducing photosynthesis.
Which two of the above were the main causes of fish mortality in the lake?