

Assertion $A$ : If $dQ$ and $dW$ represent the heat supplied to the system and the work done on the system respectively. Then according to the first law of thermodynamics $d Q=d U-d W$.
Reason $R :$ First law of thermodynamics is based on law of conservation of energy.
In the light of the above statements, choose the correct answer from the option given below :
| List$-I$ | List$-II$ |
| $(a)$ Isothermal | $(i)$ Pressure constant |
| $(b)$ Isochoric | $(ii)$ Temperature constant |
| $(c)$ Adiabatic | $(iii)$ Volume constant |
| $(d)$ Isobaric | $(iv)$ Heat content is constant |
Choose the correct answer from the options given below