Authors use dialogue, interactions, inner thoughts, and actions primarily to
a. develop characters.
b. prepare the climax.
c. flesh out the setting.
d. establish the falling action.

A.

Explanation:

A character in literature is any person, figure, animal, or an inanimate object that is present in a literary piece. There are many types of characters in a story, protagonist, antagonist, confidant, Deuteragonists, etc.

To develop a character, the author uses dialogues, interactions, actions, inner thoughts, appearance, etc. These elements help in analyzing a character and also to build it.

So, the correct answer is option A.