Assertion: The pressure of a fixed amount of an ideal gas is proportional to its temperature.
Reason: The Frequency of collisions and their impact both increase in proportion of the square root of temperature.

Options

A. If both (`A`) and (`R`) are correct and (`R`) is the correct explanation of (`A`).
B. If both (`A`) and (`R`) are correct, but (`R`) is not the correct explanation of (`A`).
C. If (`A`) is correct, but (`R`) is incorrect.
D. If (`A`) is incorrect, but (`R`) is correct.

Explanation

Assertion is true, reason is true, reason is not the correct explanation for assertion.
The pressure of a fixed amount of an ideal gas is proportional to its temperature.
`v_(rms) prop sqrt(T)`
Collision frequency is directly proportional to `v_(rms)`. On increasing the collision frequency, the pressure increases.