Function f(x) = 1 + 1.5 ln (x+1) models average number of free-throws basketball player can make consecutively during practice as the function of time, where x is number of consecutive days basketball player has practiced for 2 hours. After how many days of practice can basketball player make the average of ten consecutive free throws?
A) 424 days
B) 1531 days
C) 402 days
D) 1529 days
E)none of the above