challenge: What is the latest edition of the Chan's Colour-Illustrated Stamp Catalogue of China?
  
  A. 3-volume, 1000 page, 2005 edition
  B. 2-volume, 898 page, 2010 edition
  C. 1-volume, 500 page, 2015 edition
  D. 4-volume, 1200 page, 2018 edition
  Answer: 