Should the resistance of an ammeter be low or high? Give reason.

(A) The resistance of an ammeter should be as low as possible,ideally $0 \ \Omega$.
An ammeter is connected in series with the circuit to measure the current flowing through it.
If the resistance of the ammeter is high,it will significantly reduce the total current in the circuit due to the increased total resistance $(R_{total} = R_{circuit} + R_{ammeter})$.
Therefore,to ensure the ammeter measures the true current without altering the circuit's behavior,its resistance must be negligible.