Problem: How does the sentence end?

Mary hated anything to do with fashion unlike Katrina, because 
OPTIONS:
- Mary thought it was boring.
- Katrina thought it was boring.
Answer: Mary thought it was boring.
sentence: The man tried to put the article into his folder but the  OPTIONS:
- folder was too small.
- article was too small.
complete: folder was too small.
I wanted to learn to operate a bulldozer this summer at the mine, so I asked my uncle to show me how to operate the 
OPTIONS:
- bulldozer .
- mine .
bulldozer .
Input: Continue writing.

Nelson went to the back to get a loan from Joseph for their company because 
OPTIONS:
- Nelson was borrowing money.
- Joseph was borrowing money.

Continued: Nelson was borrowing money.
Story needs to be completed:
The worker tried to store the tool in the box but the 
OPTIONS:
- tool was too small.
- box was too small.

My choice:
box was too small.
Problem: How does the sentence end?

Randy was always cleaning better than Nelson because 
OPTIONS:
- Randy  did not used to do that for a living.
- Nelson  did not used to do that for a living.
Answer:
Nelson  did not used to do that for a living.