Problem: How does the sentence end?

Kenneth maintained concentration while Ian was constantly distracted, and therefore 
OPTIONS:
- Kenneth wrote an uneven paper.
- Ian wrote an uneven paper.
Answer: Ian wrote an uneven paper.

Problem: How does the sentence end?

Nelson got worried less often than Dennis did because 
OPTIONS:
- Nelson had issues with anxiety and depression.
- Dennis had issues with anxiety and depression.
Answer: Dennis had issues with anxiety and depression.

Problem: How does the sentence end?

My old knives would not cut through the bones because the 
OPTIONS:
- knives were very strong.
- bones were very strong.
Answer: bones were very strong.

Problem: How does the sentence end?

When Elena wanted to buy a new car, Emily offered go along because 
OPTIONS:
- Elena had purchased many new cars before.
- Emily had purchased many new cars before.
Answer:
Emily had purchased many new cars before.