Which of the following is a pollution-related disease?

Assertion : Methane,a component of greenhouse gases,contributes about $20$ percent to global warming.
Reason : The introduction of multi-point fuel injection engines in automobiles has decreased methane content in the exhausts.

Match the following columns:

Column-$I$	Column-$II$
$(a)$. Ozone thickness	$(i)$. $UV$ rays
$(b)$. $CFC$	$(ii)$. Refrigerator
$(c)$. $El$ Nino effect	$(iii)$. Temperature increase
$(d)$. Skin cancer	$(iv)$. Dobson unit

Which of the following is a secondary pollutant?

Which of the following statements is/are correct?
$I.$ Chemical fertilizers cause pollution of water bodies as well as groundwater,besides getting stored in crop plants. Therefore,environmental scientists are pressing for a switch over to organic farming.
$II.$ Organic farming is a form of agriculture that relies on techniques such as crop rotation,green manure,compost,and biological pest control.

Ahmed Khan,in collaboration with whom,developed a method to produce plastic roads?