When thomas jefferson added the louisiana territory to the united states, it existing u. s. territory.

a) doubled
b) quadrupled
c) tripled
d) extended the u. s. territory by one mile.

It doubled, we can definitely rule out D and B seems highly unlikely. I am taking a test with this question on it right now so if this is wrong i will let you know the right answer in like 10 mins.

The best and most correct answer among the choices provided by your question is the first choice or letter A.

When Thomas Jefferson added the Louisiana Territory to the United States, it doubled the existing U.S. territory.

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