December 4, 2015 7:35 am Nation's Oldest Full-Time Park Ranger Introduces President Obama Betty Reid Soskin of San Pablo, Calif., introduces President Obama at the national Christmas tree lighting ceremony. US & World Videos 0:28 A Vermont state trooper plunges into icy pond to rescue 8-year-old girl 2:59 Keep these travel etiquette tips in mind this holiday season 2:20 Bodies of Missing Men Found in Rubber Bins Inside Storage Unit 1:42 Hundreds of Golden Retrievers Walk a Mile for the Official Boston Marathon Dog 1:51 Typewriter Shop Owner Receives Gift From Tom Hanks