A definite integral ∫02x3(x4+1)5dx is to be evaluated by making the substitution u=x4+1. Which of the following gives the correct new limits of integration expressed in terms of u?
a) u goes from 0 to 2
b) u goes from 1 to 16
c) u goes from 1 to 17
d) u goes from 0 to 16