Semi Final - Four Opinions v Cat Cows

Victoria Coren Mitchell hosts the quiz where knowledge only gets you so far – logic and lateral thinking are the vital extra ingredients.It's semi-final time, and a coveted place in the third-place play-off is at stake. The teams are on form, with this sequence question being answered after just two clues: 13: Anne of Austria, 14: Maria Theresa of Spain... what comes fourth?