Which option is the clearest example of a theme? O A. The lion as a symbol of courage
O B. The story of how the world began
O C. Friends turning against each other
O D. Christine destroys her rival, Markus.

In a literary piece, a theme refers to the subject about which the piece has been written.

The clearest example of a theme is:

C. Friends turning against each other.

Theme of a story evokes the thoughts of the narrator and presents the reason behind writing the piece. The theme of the story helps in driving the central idea and concept. Theme helps in presenting the meaning and it allows a better interpretation and perception of the work. The theme is not directly stated by the writer.  

From the given options, the example of theme is 'friends turning against each other'.

Learn more about theme:

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a) he encouraged islamic schools to introduce greek texts.

d) he invited greek scholars to teach their texts to the locals.

explanation:

i am a strong (insert gender here) my father and his brother were to, they were killed not by the cold, not by the bears or wolves that roam our streets at night, but by the   bolsheviks. we must stand up and fight communism or we all end up dead, starved dehydrated, enslaved. the time is now we must fight. lenin is a dangerous man but he can be stopped. so my comrades we shall siege there weapons tonight on ward. (rides away with ak(not invented yet) and sword in hand while on bear into snowstorm)