Question

why does the formula use “$n - 1$” in the denominator?
the data is a sample and is expected to be more dispersed from the mean.
the data is a sample and is expected to be less dispersed from the mean.
the data is a population and is expected to be more dispersed from the mean.
the data is a population and is expected to be less dispersed from the mean.

Explanation:

When calculating sample variance/standard deviation, using $n-1$ (Bessel's correction) adjusts for the fact that sample data is less dispersed around the sample mean than the full population data is around the true population mean. This correction makes the sample statistic an unbiased estimator of the population parameter.

Answer:

The data is a sample and is expected to be less dispersed from the mean.