Which of the following is a theme?

A theme is a central idea or underlying message that reflects what a story is about on a deeper level. When considering the provided answer, friendship, courage, and honesty are indeed universal concepts that can serve as themes in literature. Each of these ideas can be explored in various narratives, offering insights into human relationships and moral values.

In contrast, the other options describe elements of a story but do not convey a theme. The setting and time period provide context for the story but do not express a broader message. Similarly, the main character's name is a specific detail related to character identification, rather than an overarching idea. Finally, the events that happen in a plot describe the sequence of actions or occurrences within a story, without delving into the deeper significance or moral lessons that themes typically represent. Thus, the choice of friendship, courage, and honesty as a theme is accurate as it encapsulates the moral and emotional lessons that can be derived from various narratives.