Sam was arrested for burglary and taken to the police station. after sam was booked, detective johnson administered miranda warnings. sam stated that he understood his rights, and proceeded to sign a written waiver. after answering several questions, sam said: "maybe i should speak to a lawyer before i get myself in deeper." under established supreme court rulings, detective johnson: a. must immediately terminate the interview. b. may ignore sam's request to speak with an attorney because sam has waived his right to counsel for the duration of the interview. c. must ask questions to clarify whether sam wants to invoke his right to counsel d. may ignore sam's statement and continue asking questions until sam makes an unambiguous request for an attorney.