The graph shows the exponential regression model for data representing a rabbit population after x years.

A graph shows years labeled 1 to 9 on the horizontal axis and population size on the vertical axis. A line shows an upward trend.
Which is true of the regression model?

The graph of the regression model is limited to whole-number values for x.
The graph of the regression model is limited to whole-number values for y.
The graph of the regression model cannot be used to approximate the population size for year 1.
The graph of the regression model can be used to predict the population size for any number of years in the future.