Fact 1: Vinegar can cause harm to the eyes.

Fact 2: Throughout vinegar application, wear protective eye shields.

Given the two facts above, answer the question "How can you avoid harming your eyes?" with the following options: 
- evaporation
 - focusing a lens
 - exercise
 - by indirect light
 - protect them
 - Wearing a shield
 - sweating
 - electromagnetic energy


 

      Wearing a shield   