challenge: Who were the defending champions of the mixed doubles at the 2019 BWF World Junior Championships?
  
  A. Akane Yamaguchi and Kanta Tsuneyama from Japan
  B. Chen Qingchen and Jia Yifan from China
  C. Feng Yanzhe and Lin Fangling from China
  D. Leo Rolly Carnando/Indah Cahya Sari Jamil from Indonesia
  Answer: 