How Did Edwin Chadwick's Ideas Help Decrease Disease in the Nineteenth

How did Edwin Chadwick's ideas help decrease disease in the nineteenth century?

A) The minimum wage was increased leading to improved quality of life
B) Parish workhouses where poverty-level children labored for their room and board were closed
C) Social reform legislation resulted in changes such as sidewalks
D) The new emphasis on individual responsibility encouraged people to act to protect their own health.