a
Energy stored in capacitor

\(=\frac{1}{2} CV ^{2}=\frac{1}{2} 500 \times 10^{-6} \times 10^{4}\)

\(=\frac{5}{2}\,J\)

Current will be maximum when whole energy of capacitor becomes energy of inductor.

\(\frac{1}{2} LI ^{2}=\frac{5}{2}\)

\(I =\sqrt{\frac{5}{ L }}=\sqrt{\frac{5}{50 \times 10^{-3}}}=10\,A\)