Final answer:
The uncertainty of the measurement 9.750 x 10^4 g is ±1 g because the significant figures extend to the ones place, indicating a precision of ±0.1 kg at that place value.
Step-by-step explanation:
The uncertainty of a measurement refers to the doubt concerning the value of a measurement. The measurement given is 9.750 x 10^4 g. Looking at the provided options for uncertainty, we see that the measurement is expressed to three decimal places, which suggests that the balance used to measure was quite precise. The number 9.750 x 10^4 has significant figures up to the last reported decimal place (the thousandths place), implying that the uncertainty of the measurement is in the least significant figure, which, in this case, is the ones place. Therefore, the correct uncertainty for this measurement is ±1 g, since the number is known to be at least 9.750, but less than 9.751.