Indicate whether the data are a time series or a cross section.

Number of cars sold in a dealership each day in December.

Choose the correct answer below:

A. The data are time series because the data are measured over time.

B. The data are a cross section because the data are taken from situations that vary over time but are measured at a single time instant.

C. The data are a cross section because the data are measured over time.

D. The data are a time series because the data are taken from situations that vary over time but are measured at a single time instant.