An unintended consequence of the geographic phenomena shown in the image includes all of the following EXCEPT gentrification of the area
little protection from weather conditions
rapidly spreading diseases
lack of a tax base
an underground economy

D.haka is the first answer and a.canberra is the second answer

It's either  a. chiang kai-shek and the nationalists turned against the communists and killed hundreds of them. orb. hundreds of peasants were killed in shanghai during the period of warlord rule.  if we take into account that there was warlord rule at the time, i think that it's b (not entirely sure though)just my best thoughts.