\(A B_{1} A_{2}\) and \(B_{2}\) are diatomic molecules. If the bond enthalpies of \(A_{2}, A B\) and \(B_{2}\) are in the ratio \(1: 1: 0.5\) and enthalpy of formation of \(A B\) from \(A_{2}\) and \(B_{2}\) is \(-100 \mathrm{~kJ}\) \(\mathrm{mol}^{-1}\). What is the bond energy of \(\mathrm{A}_{2}\) :
(a) \(200 \mathrm{~kJ} \mathrm{~mol}^{-1}\)
(b) \(100 \mathrm{~kJ} \mathrm{~mol}^{-1}\)
(c) \(300 \mathrm{~kJ} \mathrm{~mol}^{-1}\)
(d) \(400 \mathrm{~kJ} \mathrm{~mol}^{-1}\)