Problem: How does the sentence end?

The chair could sit on the floor but not on the stair because the 
OPTIONS:
- floor is even.
- stair is even.
Answer: floor is even.

Problem: How does the sentence end?

Using a wood router to make door frames was done only by Eric but not Benjamin because 
OPTIONS:
- Eric liked using electric tools.
- Benjamin liked using electric tools.
Answer: Eric liked using electric tools.

Problem: How does the sentence end?

Fran took the alleyway to her home instead of the sidewalk, because using the 
OPTIONS:
- alleyway made it a shorter distance.
- sidewalk made it a shorter distance.
Answer: alleyway made it a shorter distance.

Problem: How does the sentence end?

Derrick treats the workers at the factory better than  Steven, because 
OPTIONS:
- Derrick  has kindness in the heart.
- Steven  has kindness in the heart.
Answer:
Derrick  has kindness in the heart.