I would say it's mostly climate, as it determines two things: 1) what can grow/live in a given place and 2) how long can the products be kept
Additionally, it's the closeness to such things as water sources where you can fish and trade routes: a lot of European cuisines include cofee products, even if cofee is not grown in Europe!
There are many influences that could potentially lead a member of the House of Representatives to vote against the wishes of the people in their district. Simply the member could think that their constituents are incorrect in their view or don't possess enough information so therefore, they decide not to vote in accordance with the views of their constituents. Another influence could be that of their political party or the elites in their party that wish for the member to vote a certain a way. Another influence could be special interest groups or lobbies that seek to sway the views of Congress Members. These are all factors that together or separately could make a member of Congress vote in opposition of their constituents views.
A. thats not really essential
Population density is greatest in the north end part of India because of proximities to rivers and water resources, livable climates, and industrialized urban areas.