SAT Question 4618501a: Nonlinear Functions answer and explanation with Desmos solution

Choice D is correct. Substituting $0$ for $x$ in the given equation yields $f\left(0\right)=3,000{\left(0.75\right)}^0$, which is equivalent to $f\left(0\right)=3,000\left(1\right)$, or $f\left(0\right)=3,000$. It's given that the function estimates the species' population $x$ years after $2008$, so it follows that the estimated population of the species is $3,000$ in $2008$. Therefore, the best interpretation of $3,000$ in this context is the estimated initial population for this species and area in $2008$.