1940s Music History

Flipping channels last night, I paused to watch the last five minutes of Jeopardy, because if any Final Jeopardy category could cause me to wager it all, it's 1940s Music History. Well, that and maybe Popular Noise Reduction Plug-Ins. But let's be real. The Final Jeopardy answer (paraphrased):

Jerry Wexler coined this term to replace the phrase 'race music.'

The contestants answers, er, questions: What is rock and roll? What is hip hop? What is jazz?

Seriously?! No one could recall what music was popular during, I don't know, World War II and the years shortly thereafter?

Rhythm and Blues, people!!