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

Question I was asked: What is the smallest unit of an element that still has the properties of that element?

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

Question I was asked: Which of the following helps keep the Moon in its orbit?

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

Question I was asked:
Which human activity most often has a harmful effect on the environment?