If a bacterial cell culture contains 2 cells at time zero, 8 cells one hour later, 32 cells after 2 hours, and 128 cells after 4 hours, then which of the following describes the growth of this culture?

A. g = 0.5 h, v = 5 h^-1
B. g = 0.5 h, v = 2 h^-1
C. g = 2 h, v = 0.5 h^-1
D. g = 1 h, v = 1^-1