Molecule with dipole moment among the following

${\mathrm{PCl}}_3$ is polar as per VESPER theory predicts geometry is trigonal pyramidal, because of lone pair of electron in its central atom P . It is asymmetric hence indicates molecule is polar hence it has dipole moment.$\text{ The dipole moment of }{\mathrm{PCl}}_3\text{ is }0.97\mathrm{D}$.

while other three ${\mathrm{BF}}_3, {\mathrm{SF}}_6 \mathrm{and} {\mathrm{CCl}}_4$ have symmetrical shapes due to which its dipole gets cancelled and hence net dipole moment is Zero.

Hence, the correct option is option (B) ${\mathrm{PCl}}_3$.