Iran:

Between 1872 and 1905, a series of protests took place in response to the sale of concessions to foreigners by Nasser od Din and Mozaffar od Din shahs of Qajar, and led to the Iranian Constitutional Revolution. The first Iranian Constitution and the first national parliament of Iran were founded in 1906, through the ongoing revolution. The Constitution included the official recognition of Iran's three religious minorities, namely Christians, Zoroastrians, and Jews, which has remained a basis in the legislation of Iran since then.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". The Iranian Constitution did what for Christians, Jews, and Zoroastrians in Iran?
official recognition of Iran's three religious minorities