challenge: What was the voting basis for the Spanish Cortes in the 1918 general election?
  
  A. Voluntary suffrage for all citizens over 25 years old
  B. Compulsory, universal suffrage for all citizens over 18 years old
  C. Compulsory, universal suffrage for all citizens over 25 years old
  D. Voluntary suffrage for all citizens over 18 years old
  Answer: 