An unproved conclusion drawn from known facts and used as a basis of further investigation is called evidence a theory a hypothesis a method

The correct answer is hypothesis.
Hypothesis refers to your idea - an idea that you still have no evidence to prove. The idea is based on some facts, but still, you need to conduct an experiment in order to see if your hypothesis is correct or not. If it is correct, it will become a theory, but until there are evidence to support it, it remains just a hypothesis. 

Sorry, what passage, i don’t see one? i can you in pm’s if you’d like.