Apolynomial function has a root of -7 with multiplicity 2, a root of -1 with multiplicity 1, a root 2 of multiplicity 4. and a root of 4 with multiplicity 1. if the function has a positive leading coefficient and is of even degree, which statement about the graph is true?

a. the graph of the function is positive on (2,4)
b. the graph of the function is negative on (4, ∞)
c. the graph of the function is positive on (-∞, -7)
d. the graph of the function is negative on (-7, -1)