A. Partitition of India and Pakistan
B. Establishment of the caste system
C. British colonization of the Indian subcontinent
D. Gandhi's Salt March
In order: B-C-D-A
The short answer is "yes". At the time of colonization there was a
relatively endless number of jobs that needed to be completed.
Immigration simply could not keep up.
Only the federal government can regulate interstate and foreign commerce, declare war and set taxing, spending and other national policies.
It would be nice if we could know what to solve and the rest of the problem...