In an Isothermal change, the change in pressure and volume of a gas can be represented for three different temperature; T_3 \gt T_2 \gt T_1 as :

Heat and Thermodynamics PYQ — JEE Main 2023 · 24 Jan · Shift 2 · Q53 with Solution

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Correct answer: B

In an isothermal process, the temperature remains constant.
For an ideal gas, the equation is $PV = nRT$
Since $T$ is constant for a given isotherm, we get $PV = \text{constant}$ Hence, $P = \frac{\text{constant}}{V}$
Therefore, the $P$ - $V$ graph for an isothermal change is a rectangular hyperbola.
Now compare the three temperatures: $T_3 > T_2 > T_1$

For the same amount of gas, $PV = nRT$ At a given volume $V$ , $P \propto T$ So for the same volume, $P_3 > P_2 > P_1$
This means the isotherm corresponding to higher temperature lies above the lower temperature isotherm on the $P$ - $V$ diagram.
So the correct figure must show:
- three hyperbolas,
- with $T_3$ highest,
- then $T_2$ ,
- then $T_1$ lowest.
Among the given options, this corresponds to Option B.

Therefore, the correct answer is: $\boxed{\text{B}}$