Problem: How does the sentence end?

Maria bought tickets to Lima, Peru as a surprise anniversary gift for Rachel. 
OPTIONS:
- Maria couldn't wait to open the gift.
- Rachel couldn't wait to open the gift.
Answer: Rachel couldn't wait to open the gift.

Problem: How does the sentence end?

Michael was building a snowman when Donald walked by and knocked it over.  
OPTIONS:
- Michael was disappointed.
- Donald was disappointed.
Answer: Michael was disappointed.

Problem: How does the sentence end?

To avoid separation, Randy followed closely behind Kyle because 
OPTIONS:
- Randy was very familiar with the area.
- Kyle was very familiar with the area.
Answer: Kyle was very familiar with the area.

Problem: How does the sentence end?

The old man started taking medicine for his health but the 
OPTIONS:
- health was too weak.
- medicine was too weak.
Answer:
medicine was too weak.