Final answer:
The two most powerful policy-making institutions in Iran are the President and the Guardian Council, with the President being elected by the people and the Guardian Council having authority over legislation and election vetting.
Step-by-step explanation:
The two most powerful policy-making institutions in Iran are b) The President and the Guardian Council. The Iranian political structure includes both elected and unelected elements that exert control over policy making. The President of Iran is elected by the people and has significant administrative authority, while the Guardian Council, comprised of jurists who are appointed by the Supreme Leader and elected by the Islamic Consultative Assembly, has the power to interpret the constitution, vet election candidates, and approve or reject legislation passed by the Islamic Consultative Assembly (Majles). This makes the President and the Guardian Council central to the policy-making process in Iran.
The other options listed, such as the Assembly of Religious Experts, the Expediency Council, the Islamic Consultative Assembly (Majles), and the Prime Minister, also have roles in Iran’s political system, but they do not wield the same level of influence over policy making as the President and the Guardian Council.