Final Answer:
The narrator gave Kathleen a plane ticket to Vietnam as a present. Option A is the answer.
Step-by-step explanation:
The choice of a plane ticket as a present to Vietnam implies a significant and perhaps adventurous gift from the narrator to Kathleen. This option aligns with the notion of travel or exploration, as a plane ticket is a tangible item that facilitates the journey.
The act of giving a plane ticket suggests an opportunity for Kathleen to experience Vietnam, emphasizing the thoughtful and impactful nature of the gift.
The other options, such as a book, map, or necklace, would offer different connotations and experiences compared to the transformative and experiential nature associated with a plane ticket.
Option A is the answer.