The correct probability for this problem would be 1/4.
In everyday use, theory is used to mean a guess or idea about how something works. In science we would call that a hypothesis not a theory. A scientific theory is a well sustained proposal or explanation based on facts that have been repeatedly confirmed through experiments and observations. To sum up, a theory in the real world is basically a guess, and a theory in the science world is a well though out plan that has been tested and a more intact thought.
