4. This case held that it is "contradictory to argue that a defendant may be incompetent,and yet knowingly or intelligently "waive" his right to have the court determine his capacity to stand trial:"A separate competency hearing would be required to do so. A Dusky v. U.S. (1960) B Pate v. Robinson (1966) C Drope v. Missouri (1975) D Medina v. California (1972) E None of the above

The case you are referring to is B Pate v. Robinson (1966). In this case, the U.S. Supreme Court held that it is contradictory to argue that a defendant may be incompetent and yet knowingly or intelligently waive his right to have the court determine his capacity to stand trial. The Court emphasized the necessity of a separate competency hearing when there is a question about a defendant's mental competence.