Nonlinear functions SAT question

Choice D is correct. The y-intercept of a graph in the ty-plane is the point where $t=0$. For the given function $f$, the y-intercept of the graph of $y=f(t)$ in the ty-plane can be found by substituting $0$ for $t$ in the equation $y=8,000{(0.65)}^t$, which gives $y=8,000{(0.65)}^0$. This is equivalent to $y=8,000(1)$, or $y=8,000$. Therefore, the y-intercept of the graph of $y=f(t)$ is $(0,8,000)$. It’s given that the function $f$ models the number of coupons a company sent to their customers at the end of each year. Therefore, $f(t)$ represents the estimated number of coupons the company sent to their customers at the end of each year. It's also given that $t$ represents the number of years since the end of $1998$. Therefore, $t=0$ represents $0$ years since the end of $1998$, or the end of $1998$. Thus, the best interpretation of the y-intercept of the graph of $y=f(t)$ is that the estimated number of coupons the company sent to their customers at the end of $1998$ was $8,000$.

Choice A is incorrect and may result from conceptual or calculation errors. 

Choice B is incorrect and may result from conceptual or calculation errors. 

Choice C is incorrect and may result from conceptual or calculation errors.