Identify whether the statement represents an exponential function. Explain.
A population of bacteria decreases by a factor of $\frac{1}{8}$ every 24 hours.
Yes, the statement is an exponential function because the population decreases daily by a proportional rate.
Yes, the statement is an exponential function because the population decreases daily by a constant rate.
No, the statement is not an exponential function because the population decreases daily by a proportional rate.
No, the statement is not an exponential function because the population decreases daily by a constant rate.
No, the statement is not an exponential function because it is a quadratic function.