c
From the circuit it is clear that
$\mathrm{V}_{\mathrm{A}}-\mathrm{V}_{\mathrm{P}}=\mathrm{V}_{\mathrm{P}}-\mathrm{V}_{\mathrm{B}}$ and $\mathrm{V}_{\mathrm{P}}=0$
${\therefore \quad \mathrm{V}_{\mathrm{A}}=-\mathrm{V}_{\mathrm{B}}} $
Also $ \quad \mathrm{V}_{\mathrm{A}}-\mathrm{V}_{\mathrm{B}}=10 \mathrm{\,V}$
$\,\,{{\rm{V}}_{\rm{A}}} = + 5\,{\rm{V}}$ and ${{\rm{V}}_{\rm{B}}} = - 5{\mkern 1mu} \,{\rm{V}}$
