Answer: Choice B
The function is exponential.
An exponential function that models the data is f(x) =

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Step-by-step explanation:
Focus on the f(x) column.
The jump from "1" to "6" is "times 6".
The same can be said from "6" to "36" and from "36" to "216"
This heavily implies we have an exponential function. The specific function is

Plugging in x = 0 leads to y = 1, x = 1 leads to y = 6, and so on.
For the negative exponent, we have

so x = -1 works as well.