Francisco is incorrect, because the number of extrema a polynomial could have is at most one less than the degree. A polynomial of degree five can have up to four relative extrema.
In general, a polynomial of degree \( n \) can have at most \( n - 1 \) relative extrema. This is because the first derivative of a polynomial (which is used to find critical points) is a polynomial of degree \( n - 1 \), and thus can have at most \( n - 1 \) real roots (i.e., critical points). Therefore, while a degree five polynomial could have as few as zero relative extrema, it can have a maximum of four relative extrema, not five.
Thus, the correct response is: "Francisco is incorrect, because the number of extrema a polynomial could have is one less than the degree."