Which layer of the atmosphere is closest to the Earth's surface?

Which of the following diseases increases in prevalence due to the greenhouse effect?

Which gas is detected in the smoke produced due to the incomplete combustion of petrol or diesel?

Mention the components of photochemical smog and its effects.

The statements that are $TRUE$:
$A$. Methane leads to both global warming and photochemical smog.
$B$. Methane is generated from paddy fields.
$C$. Methane is a stronger global warming gas than $CO_2$.
$D$. Methane is a part of reducing smog.
Choose the most appropriate answer from the options given below:

Which is not a renewable source?