Problem: How does the sentence end?

The face of Jessica had a lot less wrinkles than Jennifer because 
OPTIONS:
- Jessica was older.
- Jennifer was older.
Answer: Jennifer was older.

Problem: How does the sentence end?

Elena had problems with their homework but Emily was able to ace theirs. 
OPTIONS:
- Elena didn't need a tutor to give them assistance.
- Emily didn't need a tutor to give them assistance.
Answer: Emily didn't need a tutor to give them assistance.

Problem: How does the sentence end?

Kayla cooked sticky white rice for Jennifer, and 
OPTIONS:
- Kayla was thanked for making such delicate rice.
- Jennifer was thanked for making such delicate rice.
Answer: Kayla was thanked for making such delicate rice.

Problem: How does the sentence end?

Ian is learning how to give first aid and he needs extra teaching hours from Samuel, because 
OPTIONS:
- Ian struggles with it.
- Samuel struggles with it.
Answer:
Ian struggles with it.