Problem: How does the sentence end?

The regulators decided to help the environment by putting taxes on the train but not the plane because the 
OPTIONS:
- train was inefficient.
- plane was inefficient.
Answer: train was inefficient.

Problem: How does the sentence end?

Lindsey felt pretty sick and needed to go to the doctor but Mary felt fine. 
OPTIONS:
- Lindsey called and made an appointment to get looked at.
- Mary called and made an appointment to get looked at.
Answer: Lindsey called and made an appointment to get looked at.

Problem: How does the sentence end?

Kayla decorated the classroom for the holidays while Erin watched. This was because 
OPTIONS:
- Kayla was the student.
- Erin was the student.
Answer: Erin was the student.

Problem: How does the sentence end?

Natalie made it clear that Megan was not welcome in their home, before 
OPTIONS:
- Natalie was kicked out for good.
- Megan was kicked out for good.
Answer:
Megan was kicked out for good.