The population of Europe doubled in the 19th century due to significant medical and scientific innovations that improved overall health and reduced disease. Key advancements included the development of vaccines and better sanitation practices, which lowered mortality rates. These improvements allowed for a greater survival rate and supported a burgeoning population. ;
The population of Europe doubled in the 19th century primarily due to major medical and scientific innovations that improved health and reduced disease. Key advancements included vaccines and better sanitation, leading to decreased mortality rates and increased population growth. Therefore, the correct answer to the question is D. Medical and scientific innovation prevented disease and increased overall health.
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