A current of $2×10^{-5} A$ produces 25 division deflection in a galvanometer. The resistance of the galvanometer coil is 4 Ω. The figure of merit of galvanometer is:

$8×10^{-7}$ ampere/division $8×10^{-5}$ ampere/division $4×10^{-7}$ ampere/division $12.5×10^{-5}$ ampere/division

$8×10^{-7}$ ampere/division

The correct answer is Option (1) → $8×10^{-7}$ ampere/division