Final answer:
The clearest example of a theme is option A: Love that is forbidden by society.
Step-by-step explanation:
The clearest example of a theme among the given options is option A. Love that is forbidden by society.
A theme is a central message or underlying idea that is explored in a literary work. In this case, the theme of forbidden love is being highlighted, which is a common theme in literature. It involves the idea of love being hindered or restricted by societal norms or expectations.
For example, in Shakespeare's play Romeo and Juliet, the theme of forbidden love is prominent as the two main characters are from feuding families, making their love difficult and ultimately tragic.
Learn more about Theme in literature