Question 3Which expression equals $ax-2by+3c$ if $x=3a-4b^2$, $y=4b-3c^2$, and $z=-2bc$?$3a^2-4ab^2-8b^2$$3a^2-4ab^2-8b^2+12bc^2$$3a^2-4ab^2-8b^2-12bc^2$$3a^2-4ab^2+8b^2+12bc^2$None of the above