A:①②
B:②③
C:③④
D:②④
① ____ A. This is cow.
② ____ B. The pig goes “oink, oink” .
③ ____ C. What’s that? It’s a chick.
④ ____ D. Eat a cake.
方程x(x﹣2)=﹣(x﹣2)的根是____ .