Final answer:
The author's purpose is to showcase the frustration that gifted children, like Thomas, can feel when faced with tasks that challenge their abilities, leading to a quick surrender due to a lack of resilience.
Step-by-step explanation:
The author's purpose for including the passage about Thomas in paragraph 5 is primarily B. To highlight that gifted children become frustrated more easily because they are not used to struggling with tasks or concepts. The passage suggests Thomas's quick surrender to challenges when outcomes do not come easily, indicating a struggle with resilience. This contrasts with children who might persist in the face of difficulty, reflecting different approaches in the nurturing of talent and self-esteem in children of varying backgrounds, as suggested by sociologist Annette Lareau and others like Mark Twain in their narratives.