The correct answer is B) to oversee the pulling-out of Israeli troops.
Prior to the bombing of the Marine barracks, the United State sent troops to Lebanon to oversee the pulling-out of Israeli troops.
On October 23, 1983, a car bomb exploded in the United States Marine Corps barracks, in the facilities of the Beirut Airport. Almost 200 U.S. marines died. The American troops were there as a peace keepers group because they supervised the withdrawal of the Palestine Liberation Organization after the Israeli invasion of Lebanon in 1982.
