If the initial population of rats was 20 and grew to 25 after two years which function best models the population P with respect to years t assuming exponential growth?

If the initial population of rats was 20 and grew to 25 after two years which function best models the population P with respect to years t assuming exponential growth?
A: P=5t²+20
B: P=5t+20
C: P=20(1.25)ᵗ
D: P=20(5)t