In the Born-Haber cycle of the given reaction $Na(s)$$ +\large \frac{1}{2}$$ Cl_2 \to NaCl(s)$ the number of endothermic and exothermic stages respectively are:

Question

\[\begin {array} {1 1} (a)\;2,3 & \quad (b)\;3,1 \\ (c)\;3,2 & \quad (d)\;2,2 \end {array}\]