[Q]: How does the sentence end?

She bought a candle instead of a book while she was unemployed because the 

[A]: candle was cheaper.


[Q]: How does the sentence end?

Matthew was explaining to Joseph how to properly build a fallout shelter.  

[A]: Joseph was impressed.


[Q]: How does the sentence end?

The piano that we just bought plays better than the keyboard because the 

[A]:
piano is in tune.