challenge: Where is Cerro del Bolsón located?
  
  A. In the Aconquija Range of Argentina, in Tucumán province
  B. In the Andes mountain range, west of the Puna de Atacama region
  C. In the eastern part of the Chilean Andes
  D. In the Puna de Atacama region, near Ojos del Salado
  Answer: 