Final answer:
A moving coil galvanometer can be converted into an ammeter by introducing the shunt resistance of a small value in parallel. (option B)
Step-by-step explanation:
To convert a moving coil galvanometer into an ammeter, which measures current, a shunt resistance is introduced in parallel. This is represented by option B.
A moving coil galvanometer typically has a low resistance and is sensitive to small currents. When it is used as an ammeter, it needs to have a lower overall resistance to measure larger currents without causing excessive deflection and damage to the galvanometer.
By adding a shunt resistance (low resistance) in parallel with the galvanometer, most of the current will flow through the shunt, allowing the ammeter to handle higher currents. The total current is divided between the galvanometer and the shunt in parallel, ensuring that the galvanometer is exposed to only a fraction of the current.
The correct method to convert a moving coil galvanometer into an ammeter involves introducing a shunt resistance of a small value in parallel (Option B). This modification allows the ammeter to accurately measure higher currents while maintaining the sensitivity of the galvanometer for precise readings.