[Q]: How does the sentence end?

Maria was perfectly happy being in a relationship with Tanya, but

[A]: Tanya didn't want to stay together forever.

[Q]: How does the sentence end?

Sarah was very good at ballet, but not Betty because

[A]: Betty practiced her dance rarely.

[Q]: How does the sentence end?

Carrie became a flight attendant, but Maria became a veterinarian instead, because

[A]:
Maria was afraid of flying.