以下选项中不能正确把cl定义成结构体变量的是______。1．typedefstruct{intred;intgreen;intblue;}COLOR;COLORcl;2．structcolorcl{intred;intgreen;intblue;};3．structcolor{intred;intgreen;intblue;}cl;4．struct{intred;intgreen;intblue;}c1;