Suppose $T = f(H)$ is the time in minutes to bake a cake at $H \ {}^{\circ} \mbox{F}$.

Which of the statements best explains the meaning of the INVERSE function $f^{-1}(T)$ ?

A. How many minutes it takes to bake a cake at $H \ {}^{\circ} \mbox{F}$
B. How many minutes it takes the oven to reach $H \ {}^{\circ} \mbox{F}$.
C. The temperature in ${}^{\circ} \mbox{F}$ of the cake after it has been in the oven for $T$ minutes.
D. The temperature in ${}^{\circ} \mbox{F}$ needed if the cake is to bake in $T$ minutes.
E. None of the above