Final answer:
Disease claimed the largest number of lives in the Civil War.
Step-by-step explanation:
Over the course of the Civil War, disease claimed the largest number of both Union and Confederate soldiers' lives. The unsanitary conditions in the army camps, lack of proper medical knowledge, and limited medical resources contributed to the spread of diseases such as typhoid, dysentery, and malaria. Soldiers were also prone to illnesses like pneumonia and tuberculosis due to exposure and malnutrition.
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