Answer:
A. All real numbers
Step-by-step explanation:
To find the domain of any graph, look at which x values are included. In the case of an exponential function, both lines in either direction will continue on forever as y approaches 0 and 1. y will never touch 0 or 1, and the infinite amout of numbers in between will always have a corresponding x value. Thus, the domain of any exponential function is (-infinity, infinity) or all real numbers.
