Final answer:
The correct choice is option (a), which is between 7491.5 and 7492.5 people, as this represents the real limits of a continuous measurement rounded to the nearest whole number.
Step-by-step explanation:
The question is centered around the concept of real limits in measurements and the reporting of population sizes with a focus on accuracy and significant figures. When we refer to the number of people visiting the Lewis and Clark exhibit being 7492, this is a discrete count and cannot have fractional components. However, when taking into consideration the uncertainty in measurements, we'd discuss real limits which pertain to the continuous nature of data and measurement. In this context, option (a), between 7491.5 and 7492.5 people, would be most suitable as it represents the real limits for a measurement of 7492 when rounding to the nearest whole number.