Problem: How does the sentence end?

James tried cutting the box with a blade but he failed, so he used a knife and it was a success. It appeared the 
OPTIONS:
- blade is sharp.
- knife is sharp.
Answer: knife is sharp.

Problem: How does the sentence end?

The carpenter used the nails on the walls and not on the doors, because the 
OPTIONS:
- doors were wobbly with them.
- walls were wobbly with them.
Answer: doors were wobbly with them.

Problem: How does the sentence end?

Rachel wanted mushrooms on the pizza, and Patricia wanted sausage, so 
OPTIONS:
- Rachel said they were allergic to meat.
- Patricia said they were allergic to meat.
Answer: Rachel said they were allergic to meat.

Problem: How does the sentence end?

We had to spray herbicide on the corn, but didn't have to for the wheat, as the 
OPTIONS:
- corn was vulnerable to disease.
- wheat was vulnerable to disease.
Answer:
corn was vulnerable to disease.