Answer :

the word that fits in the blank is theories

Answer:

theories

Explanation:

A scientific theory is a specific type of theory used in the scientific method.  A scientific theory is an unproven concept, it is a hypothesis. That is, a theory refers to a concept that needs to be explained and tested through a series of experiments. In other words, we can say that scientific theories must be supported by observations and results of many investigations and are not absolute.