Which of the following statements is true about galvanometer?

The correct answer is Option (4) → Galvanometer is a low resistance instrument

Option (1) To convert a galvanometer into an ammeter a low resistance is connected in series — Incorrect. A small shunt resistance is connected in parallel with the coil, so that most of the current passes through the shunt.

Option (2) To connect a galvanometer into a voltmeter, a high resistance is connected in parallel — Incorrect. A large resistance is connected in series with the galvanometer, so that it draws very little current.

Option (3) Galvanometer is a high resistance instrument — Incorrect. The coil of a moving coil galvanometer has a resistance of only the order of tens of ohms (for example 15 Ω or 60 Ω), which is small compared with the resistance of a voltmeter.

Option (4) Galvanometer is a low resistance instrument — Correct. Its coil resistance is only of the order of tens of ohms, so it is a low resistance instrument; a large series resistance is needed to make it a voltmeter, and a still smaller shunt in parallel to make it an ammeter.