Final answer:
In the post-transition stage of a demographic transition, a country's population is characterized by low birth rates and low death rates.
Step-by-step explanation:
In the post-transition stage of a demographic transition, the population in a country is characterized by low birth rates and low death rates. This is because the country has undergone technological advancements, improved education, and higher standards of living, which have resulted in reduced death rates and lower birth rates. Developed countries typically fall into this stage, as they have achieved stability in their population growth.