Question

Why do the building foundation have a large horizontal area of contact with the ground?

Answer 1

this is my answer OK this is right or wrong plz say me

Answer 2

I guess that this is answer may not be exact one but a correct one.
The base of the foundation of a building will have a large area in contact with the ground so as to stay right there without collapsing. A body remains much stable when the area of contact is greater or when it will have a broader base. If it does so then it will attain a state of stable equilibrium so that it doesn't topple down when a large amount of force is applied.
Hope it helps!!