How can the main idea of a text help a reader identify the theme?

a by connecting the main events of the story, a reader can conclude what lesson the author is implying about those events
b by determining the main events, a reader can understand what those characters are thinking
c by inferring the main idea of a text, a reader will understand what will happen next in the text
d by identifying the main idea of a text, a reader will find the explicit statement that is the theme

a by connecting the main events of the story, a reader can conclude what lesson the author is implying about those events