Main Answer:
The domain of an exponential function is typically all real numbers, so option 1) All real numbers is correct.
Step-by-step explanation:
An exponential function is defined for all real numbers as it can take any real number as an exponent.
The general form of an exponential function is
, where
is a positive constant and
can be any real number.
Therefore, the correct domain for an exponential function is option 1) All real numbers.