Final answer:
An ayatollah is a high-ranking Shia cleric and religious scholar in the Shia division of Islam.
Step-by-step explanation:
An ayatollah is a high-ranking Shia cleric that is an expert in the Islamic faith and the Sharia (Muslim code of law based on the Koran). They are considered as religious scholars who have reached a high rank within the Shia division of Islam. Approximately 90 percent of Iran's population follows the Shia division of Islam.