Question:
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere.
Reason $\mathbf{R}$ : Hydrogen is the lightest element. In the light of the above statements, choose the correct answer from the options given below :
Correct Option: 2,
Solution:
Most abundant gas in the troposphere is nitrogen.