Final answer:
The character with red pigtails, long stockings, and a pet monkey and horse is Pippi Longstocking from the children's books by Astrid Lindgren.
Step-by-step explanation:
The character described as a girl with red pigtails and long stockings who has a pet monkey and horse is C) Pippi Longstocking.
Pippi Longstocking is the main character in a series of children's books by the Swedish author Astrid Lindgren. Pippi is an unconventional and extraordinarily strong young girl who lives in Villa Villekulla with her monkey named Mr. Nilsson and her horse. The character is known for her playful spirit, strength, and independence. Therefore, the correct answer to the question is C) Pippi Longstocking.