Problem: How does the sentence end?

Elena's poppy seed muffins turned out burnt, but Sarah's did not, as a result of 
Answer: Elena leaving them in too long.

Problem: How does the sentence end?

I want to plant flowers in my garden and decided against roses and chose to plant columbines instead because the 
Answer: roses are harder to grow.

Problem: How does the sentence end?

Michael received a traveling visa but Joel did not, so 
Answer: Joel was not able to travel to several countries that easily.

Problem: How does the sentence end?

Bob decided to go with the lasagna over the raviolli, because the 
Answer:
lasagna was quite tasty.