challenge: What is the location of the Royal Monastery of San Juan de la Peña?
  
  A. In the city of Madrid, Spain
  B. In the town of Jaca, at the north-east of Huesca, Spain
  C. In the town of Santa Cruz de la Serós, at the south-west of Jaca, in the province of Huesca, Spain
  D. In the city of Barcelona, Spain
  Answer: 