What logarithmic function represents the data in the table? .

  x   | f(x)
 25  |  2
125 |  3 
625 |  4

From my research, the above table belongs to the question. The values in x show increasing exponential values of 5, where:

5^2 = 25
5^3 = 125
5^4 = 625

As for the case of f(x), they are the values of the powers. So the logarithmic function that would explain the values of x and f(x) would be:

A base-5 function:
f(x) = log5 x