Which food is not a staple of the indian diet?

rice

lentils

wheat

meat

Meat is the answer because generally people tend to be Hindus and being a vegetarian is quite common because killing animals (who tend to be deities, which they worship) is very wrong.

Also...

Rice grows really well in the South
Wheat grows really well in the North
Lentils are used in dal and curry

Hope this helps :)

Answerbecause of improved transportation, communication, and other advantages;