challenge: How are junior tennis tournaments in the United States typically organized?
  
  A. By school affiliation, with separate tournaments for players from public, private, and homeschools
  B. By skill level, with separate draws for beginners, intermediate, and advanced players
  C. By age group, with separate tournaments for players aged 12-and-under, 14-and-under, 16-and-under, and 18-and-under
  D. By geographic location, with separate tournaments for players from different regions
  Answer: 