The last U.S. zoo with pandas in its care expects to say goodbye to the four giant bears this fall. Zoo Atlanta is making preparations to return panda parents Lun Lun and Yang Yang to China along with their American-born twins Ya Lun and Xi Lun, zoo officials said Friday. There is no specific date for the transfer yet, they said, but it will likely happen between October and December. The four Atlanta pandas have been the last in the United States since the National Zoo in Washington returned three pandas to China last November. Other American zoos have sent...