The correct answer is "cut down on the size of each nation's nuclear arsenal."
The SALT II Treaty signed by the U.S. and Soviet Union managed to:
cut down on the size of each nation's nuclear arsenal.
The elements that were included in the SALT II Treaty were a limit in the launchers for intercontinental ballistic missiles and a ban on all new missile programs in the U.S. and the USSR.
SALT means “Strategic Arms Limitation Talks”. These were negotiations between the United States and the Soviet Union about the limitation of manufacturing missiles with nuclear weapons. The agreements were called SALT I and SALT II. The first was signed in 1972 and the second in 1979.
The Salt II Treaty limited the number of launches and based ICBM systems. The Treaty was signed by President Jimmy Carter and Soviet leader Leonid Brezhnev on June 1879, in the city of Vienna, Austria.