Answer:
c) the need to escape a sudden natural disaster
Explanation:
Voluntary migration is when a person or group of people move or are displaced. The key to getting an answer from any set of potential answers is to follow the thought process of 'did they want to move?' or 'did they have to move?'.
Job opportunities and family, while some people do consider these non-optional factors, they would not result in extreme circumstances (loss of life, persecution, imprisonment, etc.)
To receive social acceptance may mean that a person is being discriminated against, but that is not proven in context, and could also mean simply they have a negative reputation or the society they live in is discriminatory as part of their culture. While potentially dangerous, this does not always mean that a move was involuntary.
The final option, the natural disaster, is the correct answer, because a flood or hurricane, an uncontrollable factor and a cause for involuntary migration, would result in immediate, potentially sever, consequences.