challenge: What was the format of the Premiership Rugby Cup competition until 2019-20?
  
  A. The twelve Premiership teams were grouped into two pools of six, with the top two teams from each pool advancing to the semi-finals
  B. The twelve Premiership teams were grouped into three pools of four, with the three pool winners and the best runner-up entering the semi-finals
  C. The twelve Premiership teams competed in a single round-robin format
  D. The twelve Premiership teams competed in a knockout format, with each match being a single elimination
  Answer: 