A moving-coil galvanometer can be converted into an ammeter by connecting:

Correct answer: (b) A low resistance in parallel

Explanation

A galvanometer is converted into an ammeter by connecting a low resistance (shunt) in parallel with it. Most of the current passes through the shunt and only a small, safe part through the galvanometer coil, so the instrument can measure large currents. The ammeter's total resistance becomes very low, so it hardly changes the current when it is connected in series in a circuit.

A high resistance in series turns a galvanometer into a voltmeter.