Answer:
Option B, United States
Explanation:
In the stage 4 of a demographic model the rates of both birth and death are low. Therefore, the growth of population is stabilized. This situation arises because of the following factors –
a) High education
b) Strong and stable economy
c) Better health conditions
d) Increased rate of migration of people from villages to cities
e) Better employment opportunities
Hence, United states is the best option among all