Without knowing which works of literature you have read, it's difficult to build a strategic answer to that part of your question. I'll provide some ideas which I think speak to this prompt to help you think about the literature you have read.
Your thesis is basically written for you within the prompt itself. It should probably read something like this: Because of their unifying themes, ___, ___, and ___ prove to be works which speak to people regardless of life experience, and act as a mirror for readers's own life experiences.
Each body paragraph would then examine the three works you have chosen to include in your thesis, examining how each one uses themes, characters, and conflict to create a shared experience.
For example, I might choose To Kill a Mockingbird as an example. How do I then use this text to identify unifying themes? Although the novel is set close to one hundred years ago now, the conflict in the novel presents challenges that Americans still face today. Do we ever...
(The entire section contains 3 answers and 1053 words.)