Which of the following statements is consistent with poultry farming?

• A
  Modern methods like disease-free housing and pasteurization have been developed.
• B
  It is used in the manufacturing of cosmetics,dyes,polishes,and carbon paper.
• C
  It has developed as a small-scale industry in the $20^{th}$ century.
• D
  This industry involves both saltwater and freshwater environments.