$W=Z\times i\times t=\large\frac{E}{96500} $$i\times t$
$4.7=\large\frac{\Large\frac{63.5}{2}}{96500}\times$$ 1\times 5\times 60\times 60$
$\therefore i=\large\frac{4.75\times 96500\times 2}{5\times 60}$
$\Rightarrow 0.8amp$
Hence (b) is the correct answer.