Persian (local names: فارسی, Farsi IPA: [fɒːɾˈsi]; or پارسی, Parsi IPA: [pɒːɾˈsi], see Nomenclature) is an Iranian language within the Indo-Iranian branch of the Indo-European languages. It is widely spoken in Iran, Afghanistan, Tajikistan, Uzbekistan and to some extent in Iraq, Bahrain, and Oman. New Persian, which usually is called also by the names of Dari, Farsi, Parsi or Parsi-Dari, can be classified linguistically as a continuation of Middle Persian, the official religious and literary language of Sassanian Iran, itself a continuation of Old Persian, the language of the Achaemenids. [3] Persian is a pluricentric language and its grammar is similar to that of many contemporary European languages. [4] The Persian language has been a medium for literary and scientific contributions to the eastern half of the Islamic world. [ Source: Wapedia]

Hi your question should be;What is the official language of Iran? Is it arabi, pahlavi, farsi or avista?