What was the major purpose of the truman doctrine?

to contain soviet expansion

to rescue greece and turkey from communist takeovers

to end the korean police action

to provide economic stability in europe

to provide reasons for us nationalism

As far as I remember, the major purpose of the Truman Doctrine was to rescue Greece and Turkey from communist takeovers. According to the fact that the main idea was to go for nation which is being under threat from any type of authoritarian, this answer is the only suitable.
Hope it helps!

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