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.  

he is very short, and he can only reach halfway up on the elevator buttons. but on a rainy day, he has his umbrella with him, and he uses it to poke the button at the top.