c
Volume of cylinder $(V)=\pi r^{2} l$
$\frac{\Delta V}{V} \times 100=2 \times \frac{\Delta r}{r} \times 100+\frac{\Delta l}{l} \times 100$
$\frac{\Delta V}{V} \times 100=2 \times \frac{0.01}{2} \times 100+\frac{0.1}{5} \times 100$
$\frac{\Delta V}{V} \times 100=1 \%+2 \%=3 \%$