c
Heat absrobed in a thermodynamic process is given by
$\Delta \mathrm{Q}=\Delta \mathrm{U}+\Delta \mathrm{W}$
Here, $\Delta \mathrm{U}$ is same for all the three processes as it depends only on initial and final states.
$\text { But } \quad \Delta \mathrm{W}_{1}=+\mathrm{ve}, \Delta \mathrm{W}_{\mathrm{II}}=0$
${\text { and }} {\Delta \mathrm{W}_{\mathrm{III}}=-\mathrm{ve}} $
${\text { or }} {\Delta \mathrm{Q}_{1}>\Delta \mathrm{Q}_{\mathrm{II}}}$