Why were houses constructed so closely together in early nucleated settlements?
A. to maximize arable land
B. to provide protection
C. to allow neighbors to rely on each other
D. to provide equal access to water sources
Please select the best answer from the choices provided.

Answer herbicide-resistant soybeans;

1. d: oceanic crust is thicker and contains a lot of granite2.d: where two continental plates are colliding  3.b.contour boundaries4.b.plates that are attracted to each other by gravity5.a.as two continental plates collide along a convergent boundary, mountains are formed.

Rain and coal is the best way to go

They contributed many things, but here are some examples:

1) democracy - democracy as a political system was first implemented in ancient athens
2) some advances in mathematics - such as the pythagoras' law
3) the script - the roman script was adopted from ancient greek.