Answer :
Answer: The correct answer is "zeroth"
Explanation:
Zeroth law of thermodynamics: When two bodies having unequal temperatures are placed in contact, thermal energy transfers from the body having higher temperature to the one having lower temperature till the two bodies attain thermal equilibrium. Suppose, bodies A and B are in thermal equilibrium with body C, the bodies A and B will be in thermal equilibrium with each other.
There is no heat transfer between the two systems when they are at the same temperature.
Therefore, the correct option is Zeroth law of thermodynamics.