Problem: How does the sentence end?

The music was switched from old country to new-style pop at the dance because the 
OPTIONS:
- pop music was upbeat.
- country music was upbeat.
Answer: pop music was upbeat.

Problem: How does the sentence end?

The child learned much better from Leslie than they did from Benjamin, because 
OPTIONS:
- Leslie was very skilled with teaching children new things.
- Benjamin was very skilled with teaching children new things.
Answer: Leslie was very skilled with teaching children new things.

Problem: How does the sentence end?

My cousin was not able to put the cases on the shelves, because the 
OPTIONS:
- cases were too heavy.
- shelves were too heavy.
Answer: cases were too heavy.

Problem: How does the sentence end?

The guitar that I bought played better than the violin, because the 
OPTIONS:
- guitar was brand new.
- violin was brand new.
Answer:
guitar was brand new.