Shaping the writing is the correct answer.
Answer:
their
Explanation:
"own comic style" refers to both of them and not just Chico or Harpo. Therefore, it's their own comic style
First person limited means the narrator is a character in the story who can only tell the reader what they know or feel. First person POV (point of view), meaning it's narrative from the character participating in the story, be that as a main actor or bystander or something in-between.