Which is an example of a social reason for voluntary migration?
the need to expand job opportunities
the need to find a cheaper place to live
the need to live near extended family
the need to escape a depressed area

The example of a social reason for voluntary migration is the need to live near extended family

voluntary migration occur if that person move from an area on his/her own free will. Usually the reason divided between social and economic reason.

The need to expand job opportunities
The need to Find Cheaper place to live
The need to escape depressed area

These three are economic reason. . . .they do it for their economic benefit

The need to leave near extended family is the only one thats for social reasin

An example of a social reason for voluntary migration would be to live near extended family. 

The reason why this is a social reason is because it relates and talks about moving somewhere else due to family (social) issues. 

If it would involve looking for a cheaper place to live, job opportunities, or escaping a depressed area, all of this would be economic reasons.