If f is a function such that [tex]\lim_{x \to a} \frac{f(x)-f(a)}{x-a} =5[/tex], then which of the following statements must be true? A) f(a) = 5 B) The slope of the tangent line to the function at x = a is 5. C) The slope of the secant line through the function at x = a is 5. D) The linear approximation for f(x) at x = a is y = 5