Concept:Rural-urban migration is the movement of people from villages to cities, and the source region is the rural area that people leave behind.
Explanation:People migrate from the rural source region to urban centres in search of better opportunities.
As a result, the rural area steadily loses its population.
This continuous loss of people from the countryside is termed rural depopulation.
Rural employment and rural unemployment relate to job availability, not directly to the outflow of people.
Thus, the most direct effect on the source region is a decline in its population.
Answer:A. Rural depopulation