The roots of a polynomial are the values that render the polynomial to zero
y=(x+4)(x-2)^2(x+7)
in the 1st parenthesis, x=-4 render the polynomial =0
in the 2nd parenthesis, x=2 render the polynomial =0
in the 3rd parenthesis, x=-7 render the polynomial =0
So there are 3 values as roots of this polynomial (answer C)
