Sabrina is using an online calculator to calculate the outputs f(n) for different inputs n. The ordered pairs below show Sabrina's inputs and the corresponding outputs displayed by the calculator:

(1,6), (2,11), (3,16), (4,21)


Which of the following functions best represents the rule that the calculator used to display the outputs?

Af(n)= 5n-1

Bf(n)= 5n+1

Cf(n)= 4n+3

Df(n)= 4n-3