Q. Assertion: A process is called adiabatic if the system does not exchange heat with the surroundings.
Reason: It does not not involve increase or decrease in temperature of the system.

 2563  205 AIIMSAIIMS 2013Thermodynamics Report Error

Solution:

It may involve increase or decrease in temperature of the system. Systems in which such process occur, are thermally insulated from the surroundings.