Which customer come from a place with more inhabitants, customer no.0 or customer no.1?
place with more inhabitants refers to GEOID where ID = 0 OR ID = 1 and MAX(NHABITANTS_K);
SELECT T1.ID FROM Customers AS T1 INNER JOIN Demog AS T2 ON T1.GEOID = T2.GEOID WHERE T1.ID = 0 OR T1.ID = 1 ORDER BY INHABITANTS_K DESC LIMIT 1