Question

what do you mean by culture? discuss three factors that influence regional cultures. ​

Answer 1

The major reason for the diversity in India  is that the India as a single nation and as a single entity - is very young - Just 65 years old. The British was the first ever country to rule this vast sub-continent (what we call India + Pakistan + Bangladesh) under a single administrative system - 250 years back. Even then, the British were providing administration to only a few places. And a majority of the places were under administration under local Maharajas e.g. Nizam of Hyderabad, Mysore Maharaja, etc.. 

So each nation - with its own language, culture and food - never integrated with others - until the formation of a federal India in 1947 with a powerful, central executive government in Delhi.  Personally, I look at India as thousands of Nations connected by daily common threads like Cricket, British Rule, Indian Railways. 

Language:

Thanks to British, English became the administrative language of the nation. Early attempts after Independence to integrate into a single language (under Hindi - the largest spoken Indian language - but still not a majority) leds to mass protests, deaths, etc. 

Food:

Since the thousands of nations were living in a different climate region and different geographic conditions (e.g Extremely fertile Indo-Gangetic plains to Thar Desert to hilly Himalayas), the food were largely determined by the resources in hand and external influences (Mughal influences in North India to East Asian Influences in certain parts of East India and South India). 

Thanks to the recent globalization and liberalization, these differences are slowly   disappearing. 

Culture:

Culture is nothing but a summation of relgions, religions, beliefs, customs, traditions, languages, ceremonies, arts, values and the way of life. Different religious beliefs in different parts of India, languages, influences has ended up creating different nations in a single nation. 

What is ahead:

But as an Indian matures, you will see the diversity disappearing and the nation becoming a single entity.

If that helps mark my answer brainliest!