An ideal response will:
1, Note that diplomacy, which would entail negotiating with Iran to achieve an outcome that is acceptable to both the United States and Iran, is not likely to work, since it has been tried and has not worked.
2, Discuss the possible economic sanction of an embargo on Iran's main export, oil, and how that approach would be unlikely to receive international support, since it would drive up energy prices everywhere.
3, Outline the potential solution of a CIA-sponsored overthrow of Iran's government, noting that the chances of succeeding in that venture are small.
4, Discuss the option of military action. This would not be a good choice because it would lead Iran to retaliate against the United States and Israel by engaging in terrorist attacks.