Answer: SECOND OPTION.
Explanation:
Below are shown some transformations for a function f(x):
If
and
, then the function is stretched vertically by a factor of
.
If
and
, then the function is compressed vertically by a factor of
.
By definition Exponential function have the following form:

Where

Based on the explained above, you can conclude that the function
is an exponential function and it is stretched vertically by a factor of 3 (
).