(A) : Carbon-carbon bond energy values are in the order C₂H₂ > C₂H₄ > C₂H₆.

(R) : Bond energy increases with increase in the bond order.

Bond Order = no. of bonds between 2 atoms

In C₂H₂ , there is $\mathrm{C}\equiv \mathrm{C}$    bond order = 3

In C₂H₄ , there is $\mathrm{C}=\mathrm{C}$    bond order = 2

In C₂H₆ , there is $\mathrm{C}-\mathrm{C}$    bond order = 1

Bond Order is directly proportional to Bond Strength and Bond Stability, and thus Bond Energy.

More is the Bond Order, more stable the bond is hence more is the Bond Energy required to break the bond.

Thus, Bond energy increases with increase in the bond order and Carbon-carbon bond energy values are in the order C₂H₂ > C₂H₄ > C₂H₆.

So, A and R are true, R explains A.