How did the Louisiana purchase affect the United States?

It doubled the size of the USA and raised a constitutional question.

Explanation:

In 1803, the Louisiana Purchase doubled the size of the USA and raised a key constitutional question. Indeed Jefferson though a strict constitutionalist took a different different approach with this decision, he indeed took a loose constructionist approach, his interpretation of the constitution was much broader than what he had stood for. He claimed the purchase was like the signing of a treaty to prevent its looking like a violation of the constitution.

i believe the correct answer is b.

im going to go with b.