In the detailed proof, immediately after expressing `beta` as a rational function of `alpha`, i.e. `beta = f(alpha)"/"g(alpha)`, what is the very next procedural step taken in the argument:
A) The expression for `beta` is substituted into a non-zero polynomial equation `P(beta) = 0`, where P(y) has coefficients in F.
B) The equation `beta = f(alpha)"/"g(alpha)` is multiplied by `g(alpha)` to clear the denominator, isolating f(alpha) ?