I just took a test in school today. What question was I asked?

Question I was asked: Which structure is found in producers in nearly all ecosystems?

I just took a test in school today. What question was I asked?

Question I was asked: Which invention has technology that helps people keep food fresh for a long period of time?

I just took a test in school today. What question was I asked?

Question I was asked:
Which item is used for protection from chemical splashing?