Determine the Correct Exponential Function of the Form F(x) = $f ( x ) = 8 ^ { x }$

Multiple Choice

Determine the correct exponential function of the form f(x) = b^x whose graph is given.
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A) $f ( x ) = 8 ^ { x }$
B) $f ( x ) = \left( \frac { 1 } { 8 } \right) ^ { x }$
C) $f ( x ) = \left( \frac { 1 } { 2 } \right) ^ { x }$
D) $f ( x ) = 5 ^ { x }$