Physics GRE GR 1777
8. Thermodynamics (First law of thermodynamics)
In the first law of thermodynamics,
where is the amount of heat, is the internal energy, is the pressure, and is the volume of the system.
If we want to make a process that the increase in the internal energy is equal to the heat supplied, we should get rid of the second term of above equation. That means, should be zero.
The process that the equals zero is called the constant volume process, therefore the answer is (B).