$\mathrm{PF}_6^{-}$and $\mathrm{SF}_6$

$\mathrm{IO}_3^{-}$and $\mathrm{XeO}_3$

$\mathrm{BH}_4^{-}$and $\mathrm{NH}_4^{+}$

$\mathrm{BrF}_5$ and $\mathrm{XeF}_4$

(A) is true, (R) is true and (R) is the correct explanation for (A)

(A) is true, (R) is true but (R) is not the correct explanation for (A)

(A) is true but (R) is false

(A) is false but (R) is true

phenol

benzoic acid

para-nitrophenol

2-hydroxybenzoic acid

$\mathrm{BF}_3>\mathrm{BeCl}_2>\mathrm{SF}_6>\mathrm{SiCl}_4$

$\mathrm{BeCl}_2>\mathrm{SF}_6>\mathrm{SiCl}_4>\mathrm{BF}_3$

$\mathrm{BeCl}_2>\mathrm{SiCl}_4>\mathrm{BF}_3>\mathrm{SF}_6$

$\mathrm{BeCl}_2>\mathrm{BF}_3>\mathrm{SiCl}_4>\mathrm{SF}_6$