See image — AITS & Test Series Chemistry Question

💡 Solution & Explanation

The stability decreases in the order: cyclohexane (I)>cyclopentane (II)>cyclobutene. Further, trans-1, 2-dimethylclobutane (IV) is more stable than cis-1, 2-dimethylcyclobutane (III). Thus, stability decreases in the order: I > II > IV > III. Therefore, their heat of combustion decreases in the reverse order: III > IV > II > I.