If many people leave an area after a disaster, what type of effect does this show?

Correct answer: Out-migration driven by a push factor

The correct answer is A: out-migration driven by a push factor. A disaster such as a flood, cyclone or severe drought can make the place of origin unsafe or difficult to live in. This unfavourable condition pushes people away, so the disaster acts as a push factor. Because the people leave their original area, the movement is called out-migration from that area. B describes people entering a place because a favourable feature attracts them; that is the opposite direction. C refers only to births minus deaths and does not include movement between places. D means more births per population, whereas disaster-related departure is a migration event, not a birth event. A useful warning is that push and pull describe reasons, while in-migration and out-migration describe direction: people are pushed out of the source area and may be pulled toward a safer destination.