The bond dissociation energy of B – F in BF3 is 646kJ mol–1 whereas that of C – F in CF4 is 515kJ mol–1. The correct reason for higher B – F bond dissociation energy as compared to that of C – F is
(a) smaller size of B-atom as compared to that of C-atom
(b) stronger σ bond between B and F in BF3 as compared to that between C and F in CF4
(c) significant pπ-pπ interaction between B and F in BF3 whereas there is no possibility of such interaction between C and F in CF4.
(d) lower degree of pπ-pπ interaction between B and F in BF3 than that between C and F in CF4.