Correct option is (a) 3.4 kcal
Explanation: Using the equation ΔG = ΔH – TΔS, where G is represented by the Gibbs free energy, H is represented by the change in enthalpy, T is represented by the temperature and S is represented by the entropy. ΔH = ΔG + TΔS = 3.4 kcal – 293 x 2.4 cal/K = 3.4 kcal.