When the 1987 INF treaty was concluded between the United States and the Soviet Union, the two world superpowers agreed to _______________________.

A) limit the number of nuclear warheads on each intercontinental ballistic missile
B) limit their production of weapons-grade plutonium
C) demilitarize outer space
D) destroy all their land-based intermediate-range nuclear missiles in Europe

The 1987 INF treaty (Intermediate-Range Nuclear Forces Treaty) was an agreement between the United States and the Soviet Union to eliminate all their land-based intermediate-range missiles in Europe. The treaty aimed to reduce the threat of nuclear war in Europe and improve relations between the two superpowers. It did not limit the number of warheads on intercontinental ballistic missiles, limit production of weapons-grade plutonium, or demilitarize outer space.