The derivative of a polynomial p(x) at x=3 is −4. Which of the following statements best describes the behavior of p(x) near x=3?
a) The graph of p is increasing at a rate of 4 units per unit change in x.
b) The y-coordinate of the tangent line at x=3 is −4.
c) The graph of p is decreasing at a rate of 4 units per unit change in x.
d) The graph of p has a horizontal tangent at x=3.