By David Beasley ATLANTA, Nov 26 (Reuters) - Cigarette smoking among U.S. adults last year touched its lowest on record, a drop spurred by higher prices, smoke-free policies and anti-smoking campaigns, the Centers for Disease Control and Prevention said on Wednesday. About 17.8 percent of American adults smoked cigarettes in 2013, down from 20.9 percent in 2005 and 42.4 percent in 1965, when the U.S.