LOS ANGELES — CBS says the big reveal is coming for “How I Met Your Mother.” The network said Wednesday the sitcom will air its ninth and final season this autumn. And CBS Entertainment President Nina Tassler promised that TV's “most mysterious mother” will be unveiled as the show wraps up. That would be the mystery woman with whom Ted, played by Josh Radnor, ultimately has a family. The sitcom's cast also includes Neil Patrick Harris, Cobie Smulders, Jason Segel and Alyson Hannigan. 20th Century Fox Television says all the actors will return for the 2013-14 season. – AP