Final answer:
None of the provided scenarios describe Caitlin running to her mother, hence none of the options (A to D) can be confirmed as the correct answer to the question.
Step-by-step explanation:
Based on the provided information, none of the scenarios describe Caitlin running to her mother. Therefore, it is not possible to choose any of the options (A to D) as the correct answer for the question "Why did Caitlin run to her mother?" Instead, the narratives given reveal various experiences of Caitlin, which include feeling isolated while visiting her friend Maria's family in Madrid, showing symptoms of homesickness, and deliberating on social and family dynamics in different contexts, but none depict Caitlin running to her mother for any of the suggested reasons.