Answer:
a. Author's point of view.
Step-by-step explanation:
Pronouns are those words that we use in place of the nouns, in order to prevent the use of repetition over the same noun. They are also different kinds of pronouns, depending on their uses.
In a text, pronouns provide the clue to the author's point of view. This means that readers can know who is the narrator or what point of view is used in the story by the pronouns used. For instance, if the narrative voice uses the personal pronoun "I", then we can know that the narration or point of view is in the first person. Similarly, depending on the use of the pronouns, we can know that the narration is third person, or omniscient, or an absent narrator, etc.
Thus, the correct answer is option a.