Given the functions f(x) = log2(4x) and g(x) = 4x² - 3, which of the following statements is true?
a) Both f(x) and g(x) have a common domain on the interval (0, [infinity]).
b) Both f(x) and g(x) have the same range of (-[infinity], 0].
c) Both f(x) and g(x) have the same intercept of (2, 0).
d) Both f(x) and g(x) increase on the interval of (-[infinity], 4].