Correct Answer - B
On moving down the group, electron affinity must decrease, because of the increase in the size of the atom. However, fluorine has lower electron affinity than chlorine. A low value of electron affinity for fluorine is due to the small size of F atom. In a compact 2 p-orbitals. of F, the added electron does not feel much attraction, because of inter-electronic repulsion between the electrons already present in small compact 2p-subshell of F atom.
