Okla. Stat. tit. 12, § 12-1143: Answer in action to recover real property

It shall be sufficient in such action, if the defendant in his

answer, deny, generally, the title alleged in the petition, or that

he withholds the possession, as the case may be, but if he deny the

title of the plaintiff, possession by the defendant shall be taken

as admitted. Where he does not defend for the whole premises, the

answer shall describe the particular part of which defense is made.