Final answer:
The correct option is A) Temperature is constant (isothermal process)
An isothermal process refers to a process where the temperature remains constant while the volume and pressure change. Example of an isothermal process and an isochoric process.
Step-by-step explanation:
An isothermal process refers to a process where the relationship between pressure and temperature is constant. In this process, the temperature of the gas remains constant while the volume and pressure change. An example of an isothermal process is the expansion or compression of an ideal gas in a piston-cylinder assembly that is in contact with a heat bath maintained at a constant temperature. During an isothermal process, the gas follows the equation PV = constant.
On the other hand, an isochoric process refers to a process where the volume remains constant while the pressure and temperature can change. A common example of an isochoric process is the heating of a fixed amount of gas in a rigid container, where the pressure of the gas increases due to the increase in temperature.
Therefore, the correct option for the given question is A) Temperature is constant (isothermal process) and B) Volume is constant (isochoric process).