How did the Iran hostage crisis end

this is the answer down below.

Explanation: The crisis ended with the release of the hostages after a captivity of 444 days, from November 4, 1979 to January 20, 1981. ... 11 February 1979 – The Iranian monarchy was dissolved and the Ayatollah Khomeini was granted supreme power. This day later became a new national holiday in Iran.

to contain the wave of communism

i think its provide for the common defense