Question: How to purify your water manually?

  Options: 
 A. For water purification, carry a Katadin water purifier without spare filter element and Potable Aqua water purification tablets. They can purify up to 500 liters of water each,
 B. For water purification, carry a Katadin water purifier with spare filter element and Potable Aqua water purification tablets. They can purify up to 500 liters of water each,
Answer: B