challenge: What was the composition of Li's army when he set out in the autumn of 102 BC?
  
  A. 60,000 penal recruits and mercenaries, with 30,000 horses
  B. 10,000 soldiers and 50,000 supply animals
  C. 30,000 penal recruits and 60,000 mercenaries
  D. 100,000 oxen and 20,000 donkeys and camels
  Answer: 