My research question: "does socialization have significant effects on development of aggression towards women in later life among men"

I need to narrow down my definition of socialization and find one aspect of it to measure from what I am told. How can I change my research question to include one aspect of socialization to measure? (what would the new research question be?) And what would be 3 sub questions to follow? It is important that the one aspect is researchable. When writing my proposal I would need to know if I should use individuals, groups, or organizations. Any other information that would be useful is appreciated.