If most people can survive only a few days without a combination of hydrogen and oxygen, then most people can survive only a few days without a combination of what?

Answer choices:
- dehydration
 - hydrogen and oxygen
 - food and shelter
 - hydrogen chloride and water
 - scarce resources
 - solid, liquid, gas
 - lemonade and ice water
 - watercolor paints

 

  hydrogen and oxygen        