Which of the following factors most contributed to the shorter life span of those living in cities as opposed to those
in the country? source:

The correct answer for this question should be Illness caused by unhealthy living conditions

The shorter life span of those living in cities as opposed to those  in the country because of the illness caused by unhealthy living conditions.

hi,

john hunter was a scottish surgeon, he was a early advocate of careful observation and scientific method in medicine,

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