A phenomenological analysis of a Teacher's Perceptions of Ethical Factors Affecting Teacher-Student Relationships if you do not name/know the name of the teacher that you are referring to.
or
A phenomenological analysis of a Group of Teachers Perceptions of Ethical Factors Affecting Teacher-Student Relationships. If you do not name/know the names of the teachers that you are referring to
A phenomenological analysis of The Perceptions of Ethical Factors Affecting the Teacher-Student Relationship if you know the name of the teacher that you are referring to and you intend to name that teacher in your paper.
or
A phenomenological analysis of The study Group of Teachers Perceptions of Ethical Factors Affecting Teacher-Student Relationships. If you name/know the names of the teachers that you are referring to.
A phenomenological analysis of the Teachers’ Perceptions of Ethical Factors Affecting the Teacher-Student Relationships is not correct in any case.