Only hours into her trip, Joan _______ cut her holiday short after receiving distressing news from home.

1. ought to

2. had to

3. might

4. can

'~해야 한다'라는 의미로 조동사 had to가 정답이라고 나와있는데

ought to 역시 ~해야한다 라는 의미인데 정답이 될 수 없는건가요?