Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: A student observes cells in an object by using a microscope. The student thinks that the object was part of a living thing. Which statement explains why cell theory can be used to support the student's thinking?
Cell theory states that all living things are made of cells.
The student's observation of cells supports the fundamental tenet of cell theory that all living organisms are composed of cells.