What case does the antagonizing speaker make about the possibility of accepting Ender into the academy?

I'm thinking that you are referring to the beginning of the book when Graff visits Ender's family to take Ender away. His parent's don't particularly want to give their son away but have little choice. Graf reminds them that they were allowed to have a "third" specifically for this reason. Graff, rather brashly, states that this visit with the parents is merely a courtesy by the army and that they have no choice in the matter.