Low resistance is linked in parallel to an ammeter to improve its range so that the equivalent resistance is lower, allowing the device to pass through all of the circuit's currents and measure current with greater precision.
The total resistance in the circuit decreases when more parallel resistances are added to the lines. Because Ohm's Law indicates that the lower the resistance, the higher the current, as you add additional branches to the circuit, the overall current will increase.
By connecting a suitably low resistance parallel to the ammeter, the ammeter's range can be expanded. Thus, the effective resistance is decreased.
The current flow through the ammeter is increased when the resistance is reduced.
Hence, this is the way to increase the range of an ammeter.
