A university introduced a group of young teachers. Some of the teachers in the physics department have a doctorate degree. The physics teachers who have obtained a doctorate degree have more than three years of teaching experience. Some female teachers also have more than three years of teaching experience. All female teachers have married. Based on the above text, Which of the following optionsns must be correct:. ['All physics teachers have more than three years of teaching experience.', 'All Physics teachers who have obtained a Ph. D. are married.', 'Physics teachers who may have obtained a Ph. D. degree are female teachers.', 'There may be male teachers who are not yet married.']