What Was Ironic About the Final Outcome to President Carter's

What was ironic about the final outcome to President Carter's handling of the Iranian hostage crisis?

A) The American hostages were not released until minutes after Ronald Reagan was sworn in as president, thus denying Carter a final triumph.
B) The hostages were killed after President Carter authorized an unsuccessful rescue mission by Special Forces in April 1980.
C) The Shah of Iran died of cancer before Carter could return him to Iran in exchange for the hostages.
D) Even though the United States pledged not to interfere in Iran's domestic affairs after the release of the hostages, it still continued to do so.