Mathematics for IGCSE & O level - Using A Calculator (Section 1 - No. 17)

In the context of a calculator, what does 'significant figures' refer to?

The number of digits to the right of the decimal point.

All digits in a number except leading zeros.

The total number of digits in a number.

Digits in a number that contribute to its precision.

Significant figures indicate the precision of a measurement or calculation.