Correct option is B Balz-Schiemann reaction
EXPLANATION:
Balz-Schiemann reaction is used to prepare aryl fluorides from diazonium salts and fluoroboric acid.
$
\mathrm{Ar}-\mathrm{N}_{2} \mathrm{X} \stackrel{\mathrm{HBF}_{4}}{\longrightarrow} \mathrm{Ar}-\mathrm{N}_{2} \mathrm{BF}_{4}^{-} \stackrel{\Delta}{\longrightarrow} \mathrm{Ar}-\mathrm{F}+\mathrm{BF}_{3}+\mathrm{N}_{2} \uparrow
$