Answer:
A
Step-by-step explanation:
A linear function increases/decreases by a certain amount every year. As it changes 1500 over the first 5 years (300 per year) and 3000 over the next 5 (600 per year), this cannot be liner
A quadratic function goes down then up, or vice versa. This consistently goes up, and is therefore not quadratic
A trigonometric function also goes up and down, so it is not trigonometric
Therefore, as an exponential function can keep going up at different rates over time, this is an exponential function