[Q]: How does the sentence end?

The computer was stumped by the algorithm but solved the equation with ease, as the 

[A]: equation was so simple.


[Q]: How does the sentence end?

The girl put the history book back on the shelf and read the magazine because the 

[A]: book was boring.


[Q]: How does the sentence end?

Mary left the envelopes in the basket and focused on addressing the postcards, because the 

[A]:
envelopes were nonurgent.