NEET UG PHYSICS MCQ: THERMODYNAMICS

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: Efficiency of a reversible heat engine will be highest at $- 273^\circ C$ temperature of cold reservoir.

Reason R: The efficiency of Carnot’s engine depends not only on temperature of cold reservoir but it depends on the temperature of hot reservoir too and is given as $\eta = \left( {1 - \frac{{{T_2}}}{{{T_1}}}} \right)$.
In the light of the above statements, choose the correct answer from the options given below