Answer:
f(x) = (8/3)^x
Explanation:
Since f increasing, the base value must be greater than 1.
8/3 is the only base value greater than 1.
The base (3/8) would be a decreasing graph because it is less than 1.
The base (-3/8) would result in a wavering graphing passing the x-axis many times. (Because whether the result is negative depends on if x is odd or even.)
in (8/3)^(-x), it is the same as (3/8)^x by applying the negative exponent rule a^(-x) = 1/(a^x).