For the questions you've provided, here are the correct options:
Question 17: Which of the following would you order at the end of the meal?
- postre (This means "dessert," which is typically what you order at the end of a meal.)
Question 18: Yo _____ en taxi.
- vengo (This translates to "I come" and is the appropriate first-person singular form of the verb "venir.")
Question 19: Elena no ______ traer el postre.
- puede (This means "can" or "is able to," and it's the correct form for Elena in the singular third person.)
Let me know if you need more assistance!