The decomposition of organic compounds in the presence of oxygen and without the formation of odoriferous substances is called:

How can domestic waste be used as manure?

The radical which mainly causes ozone depletion in the presence of $UV$ radiations is:

Green plants use carbon dioxide during photosynthesis and release oxygen,yet carbon dioxide is considered responsible for the greenhouse effect. Why?

Excess nitrate in drinking water can cause

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R:$
Assertion $A:$ Polluted water may have a value of $BOD$ of the order of $17 \, ppm$.
Reason $R:$ $BOD$ is a measure of oxygen required to oxidise both the biodegradable and non-biodegradable organic material in water.
In the light of the above statements,choose the most appropriate answer from the options given below.