Durant and Westbrook are playing a three-point challenge game to improve long
distance shooting. Each time each of them makes a basket, 3 points are added to
their respective scores. Durant has 18 points and Westbrook has 12 points.
Which of the following options has the pair of explicit formulas that represents the
number of points for each player as an arithmetic sequence?
A: Durant: 18 +(n-1)(3)
B: Durant: 18-(n-1)(3)
C: Durant 18+(n-3)
D: Durant 18+3n