Which statement is true?

(a)If the x-intercept of a line is given by (0, b), b can never equal zero.
(b)A line of x = a (where a is not zero) cannot have a y-intercept.
(C)If the y-intercept of a line is given by (a, 0), a can never equal zero.
(d)A line with a zero slope cannot have a y-intercept.