A bouncing toy reaches a height of 64 inches at its first peak, 48 inches at its second peak, and 36 inches at its third peak. Which explicit function represents the geometric sequence of the heights of the toy?
A. f(x)=64(5/6)^x-1
B. f(x)=48(5/6)^x-1
C. f(x)=64(3/4)^x-1
D. f(x)=48(3/4)^x-1