d) More and more people are choosing to live in cities.
a) They offer better opportunities, better services, and sanctuary from conflict and the effects of climate change influences.
c) Yet large numbers of people are unable for various reasons to move to cities — skills mismatches, reluctance to sell land at a loss, and sometimes because of explicit policy restrictions that limit people’s movement within countries.
b) These choices have major implications for a person’s standard of living, particularly in developing countries.