A particle of mass $m$ is projected with a velocity $v$ making an angle of $45^{\circ}$ with the horizontal. The magnitude of angular momentum of the projectile about an axis of projection when the particle is at maximum height $h$ is
(a) Zero
(b) $\frac{m v^{2}}{4 \sqrt{2} g}$
(c) $\frac{m v^{2}}{\sqrt{2} g}$
(d) $m \sqrt{2 g h^{3}}$