The sensitivity of a galvanometer that measures current is decreased by $\large\frac{1}{40}$ times by using shunt resistance of $10 \;\Omega$. Then, the value of the resistance of the galvanometer is

Question

$$(a)\;400\; \Omega \quad (b)\;410\; \Omega \quad (c)\;30\;\Omega \quad (d)\;390\;\Omega$$