Which statement best describes f(x)=
A. 6 is in the domain of f(x) but not in the range of f(x).
B. 6 is not in the domain of f(x) but is in the range of f(x).
C. -6 is in the domain of f(x) and in the range of f(x).
D. 6 is neither in the domain of f(x) nor in the range of f(x).