Step-by-step explanation:
look at the graph !
there is an explicit horizontal limit line at y = -1.
no such vertical line for a limit for x.
as usual for exponential functions, f(x) grows rapidly, but is still valid for all x of R.
so, D is the right answer.
when x gets more and more to the left, f(x) grows and grows strongly, and goes to infinity.
when x gets more and more to the right, f(x) gets closer and closer to -1 (but will never reach it, only at infinity ...).
