Hello!
the correct option is:
b. a value of the variable that makes the polynomial equal to zero.
why?
the root or roots of a polynomial are the values of the variable that makes the polynomial equal to 0. we can find the roots of a polynomial making the expression equal to 0 and then, isolating the variable (it it has just one variable).
for example, given the following polynomial:
![3x-6](/tex.php?f=3x-6)
the root or zero of the polynomial, can be found by making the expression equal to 0, and then, isolating the variable, so, finding the root we have:
![3x-6=0](/tex.php?f=3x-6=0)
![3x=6](/tex.php?f=3x=6)
![x=\frac{6}{3}=2](/tex.php?f=x=\frac{6}{3}=2)
therefore, we have that the root of the polynomial is equal to 2.
we must remember that the number of roots that a polynomial can have, will depend on the degree of the polynomial, a first degree polynomial have will have one single root, a second degree polynomial (quadratic expression) may have two roots and so.
hence the correct option is:
b. a value of the variable that makes the polynomial equal to zero.
have a nice day!