What is the main idea of this passage？A．The progress of medicine has improved the health o

What is the main idea of this passage？

A．The progress of medicine has improved the health of ordinary people to the level of the rich in the 19th century.

B．The industrial revolution reduced disease and death by providing better medicine, washable fabric and richer nutrition.

C．Improvements in medicine, personal hygiene and nutrition together greatly improved people"s health and life expectancy.

D．Our knowledge about diseases and nutrition has greatly improved since the 19th century.

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