Correct Answer  Option 2 : v
rms ∝ √T
The correct answer is option 2) i.e. vrms ∝ √T
CONCEPT:

Rootmeansquare (rms) speed: The rootmeansquare speed is a measure of the speed of gas molecules taking into account their molecular weight and temperature.
 It is defined as the square root of the average velocitysquared of the gas molecules.
It is given by the equation:
\(v_{rms} = \sqrt{\frac{3 RT}{M}}\)
Where R is the universal gas constant = 8.314 J mol1 K1, T is the temperature of the gas and M is the molecular mass of gas.
EXPLANATION:
We know that, \(v_{rms} = \sqrt{\frac{3 RT}{M}}\)
∴ vrms ∝ √T