A rapid population increase causes significant issues in countries with low economic growth due to the strain it places on resources and services. This often leads to heightened poverty and inadequate access to education and jobs. In contrast, low unemployment and a higher standard of living are generally seen as beneficial outcomes. ;
The most problematic issue in countries with low economic growth is typically a rapid population increase. This growth strains resources, leading to poverty and inadequate access to essential services, while low unemployment and a higher standard of living are generally positive signs. Thus, the answer is D. rapid population increase.
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