D. Increased porosity (allows extra oxygen and water)
Place a teaspoon of salt in a bottle cap or small cup and dampen it with a few drops of water (without dissolving it). Carefully place the wet salt and the hygrometer inside a see-through container and close tightly. You can use a zip lock bag provided it seals well and you leave some air inside as well
Presence of oxygen aerobic process
Your answer is most likely C
