Which soap opera is set in the fictional town of Genoa City?

In 'Knots Landing', from which show did the series spin off? Which prime-time soap opera was a spin-off of 'Beverly Hills, 90210'? Which daytime soap opera debuted on NBC in 1965 and is known for its hourglass opening? Which soap opera is set in the fictional town of Port Charles? Which late-night show did Conan O'Brien host from 1993 to 2009 on NBC? Which comedian became host of 'The Tonight Show' in 2014? Which comedian hosted 'The Late Late Show' on CBS from 2015 to 2023? Which HBO weekly show is hosted by John Oliver?