Answer: A. Bond breaking is endothermic (energy is used in); bond making is exothermic (energy is released out). The overall \(\Delta H\) equals the energy used in breaking reactant bonds minus the energy released in forming product bonds.
Here \(\Delta H = -120\) kJ/mol — negative, so the reaction is exothermic. By rearrangement, the energy released in forming new bonds must be greater than the energy used in breaking the old ones, by 120 kJ/mol. Option A states exactly this.
B reverses the inequality — that would describe an endothermic reaction (\(\Delta H > 0\)). C is a category error: bond breaking absorbs energy, it doesn't release it, so 'energy released in breaking bonds' is meaningless. D similarly reverses which process absorbs and which releases energy.
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