Melanie used cross multiplication to correctly solve a rational equation. She found one valid solution and one extraneous solution. If 3 is the extraneous solution, which equation could she have solved?

A.
The equation is
=
because 3 makes a denominator equal zero and is not a solution of the equation derived from cross multiplying.
B.
The equation is
=
because 3 makes a numerator equal zero and is a solution of the equation derived from cross multiplying.
C.
The equation is
=
because 3 makes a denominator equal zero and is a solution of the equation derived from cross multiplying.
D.
The equation is
=
because 3 is a solution of both the original equation and the equation derived from cross multiplying.