Forming a hypothesis is accomplished deductive reasoning abductive reasoning inductive reasoning subjective reasoning

The correct answer is inductive reasoning.  

A method of reasoning in which the premises are observed as providing some kind of proof for the certainty of the conclusion. While there is certainty in the conclusion of a deductive argument, and there may be a likelihood in the truth of the supposition of an inductive argument, on the basis of the given proof.  

In inductive reasoning, a conclusion is drawn from various observations regarding a probable common reason and generating a general rule.  

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.