Answer:
I believe the best option is sunk cost fallacy.
Step-by-step explanation:
The sunk cost fallacy refers to the likelihood of people and companies continuing with their projects because they have already invested a lot of time and money in it. Even if the most efficient decision is to abandon that project for a new one, it is common for people to refuse to do so, insisting in pursuing the expected result from the project they've invested so much in. That is what Maeve is doing. Even though she wants to change majors, she won't do it due to the time she has spent in this one. Even if it is making her unhappy, she will stick to her decision.