Final answer:
More-developed countries tend to have lower total fertility rates than less-developed countries due to increasing levels of industrial activity and urban growth.
Step-by-step explanation:
The true statement about total fertility rates and countries is that more-developed countries tend to have lower total fertility rates than less-developed countries. This is because as countries experience increasing levels of industrial activity and urban growth, there is usually a higher standard of living and a decrease in family size.
For example, a rural-to-urban shift takes place, driven by the pull of opportunities and advantages in industrializing and urbanizing areas. While there are exceptions, a decrease in family size usually coincides with a higher level of urbanization.
It is important to note that total fertility rates vary across countries and regions, and factors such as access to birth control and education also play a role in determining fertility rates. So, while more-developed countries generally have lower fertility rates, there can be variations within and between countries.