Answer
(c) zero, infinity
Work Step by Step
Since ammeter measures current so it should have negligible resistance else current will decrease (as its resistance will add up to the equivalent resistance of the circuit). And ideal ammeter has zero resistance.
As voltmeter measures potential drop so it should have large resistance so that negligible current will pass through it. In ideal voltmeter resistance is infinity so that no current passes through voltmeter and it will measure
actual potential drop.
