Final answer:
The uncertainty associated with a measurement of 124.49 ohms provided in the options is ± 0.01 ohms, reflecting the least count of the instrument and the range within which the true value is expected to lie.
Step-by-step explanation:
The uncertainty associated with an instrument can be defined as how much the measured values might deviate from the standard or expected value. It is expressed as a range around the measured value within which the true value lies. Considering the measurement 124.49 ohms, and the options provided for the uncertainty, we must look at the least count or the finest division that the measuring instrument can reliably measure to determine the uncertainty. If the instrument measures to the nearest 0.01 ohms, the uncertainty would be ± 0.01 ohms since the true value could slightly vary within this range due to limitations in precision. The correct option reflecting this measurement uncertainty is option b: ± 0.01ohms.