Answer:
It's changeable
Before the microscope, Linnaeus classified organisms only separated in two kingdoms, while more were introduced later. So, they were only classified in two kingdoms, they can be changed and classified to more than two.
I think all of the above...
because I know they built aqueducts and sewers, so since 2 of they are correct, then all 3 must be.
What is your question? I can help!
