(Simple Interest and Arithmetic Sequences LC)

An arithmetic sequence begins with 65, 56, 47, 38, 29...
Which option below represents the formula for the sequence?

A. f(n) = 56 - 9(n)
B. f(n) = 56 +9(n-1)
C. f(n) = 65 +9(n-1)
D. f(n) = 65-9(n-1)