Which of the following statements is true about the silver platter doctrine?
1) The silver platter doctrine was the process whereby evidence was "served" by state law enforcement officers to federal prosecutors on a "silver platter."
2) The silver platter doctrine was used by federal agent to circumvent the exclusionary rule.
3) The silver platter doctrine was ruled unconstitutional by the U.S. Supreme Court in 1960 in Elkins v. United States.
4) Only a and b are true.
5) All of the above statements are true.