PhSNa replaces F from o- and p-dinitro- fluorobenzene via nucleophilic aromatic substitution.

PhSNa replaces Cl from compound D via nucleophilic bimolecular substitution reaction.

In case of compound B and C, nucleophilic substitution is not possible neither by S_NAr or S_N2 . because, the electron withdrawing group is present at meta-position and halogen is attached to sp²-carbon.

Positive Carius test is given by compound containing halogen, sulphur and phosphorus. So, only compound A and D reacts with PhSNa to gives a positive Carius test on treatment with Na₂O₂ followed by addition of BaCl₂.