Which development resulted in the spread of disease and increased mortality rates during the industrial revolution?
a. development of pasteurization
b. spread of social reform movements
c. increased social stratification
d. overcrowding in cities

One of the things that resulted in the spread of disease and increased mortality rates during the Industrial Revolution was the "Overcrowding in cities," since this meant that diseases did not have to travel very far in order to infect their next host. 

Ithink it would be india, assuming you're on a usa test prep question. let me know if i'm right or wrong.