Sectional differences were increased:

a. as the northeast developed into a strong industrial center

b. when invention of the cotton gin made cotton more profitable

c. when pioneers moved west and demanded internal improvements

d. all of the above

The correct answer is A) as the Northeast developed into a strong industrial center.

Sectional differences were increased as the Northeast developed into a strong industrial center.

The problem was that the southern states relied so much on slavery to produce the kind of crops in the large plantations needed for trade and to be exported to Europe. That is why southerners were against abolition. On the other hand, northern states developed the kind of industry that allowed them to produce more and better products due to new manufacturing procedures. That is how the Northeast developed into a strong industrial center.