Question

linear function, of the form f(x) = mx + b cubic function, of the form f(x) = ax³ + bx² + cx + d exponential function, of the form f(x) = a·bˣ + c reciprocal function, of the form f(x) = \frac{a}{x} root function, of the form f(x) = a\sqrt{bx} + c

Explanation:

The plotted data shows a curve that increases rapidly at first, then the rate of increase slows and approaches a horizontal asymptote. This matches the growth pattern of a root function, where growth decelerates as $x$ increases, unlike linear (constant rate), cubic (accelerating growth), exponential (continuous accelerating growth), or reciprocal (decreasing) functions.

Answer:

root function, of the form $f(x) = a\sqrt{bx} + c$