5. If f(x) = x? + 5, which of the following is equal to g(x) = f(x + 1) ?
A.g(x) = x2 + 2x + 6
B. g(x) = x2 + 6
C. g(x) = x2 + 2x +1
D. g (x) = x2 + 2x + 5