Final answer:
The Edict of Milan, issued in 313 CE by Emperor Constantine, legalized Christianity and ended persecution of its followers in the Roman Empire.
Step-by-step explanation:
The document issued in 313 CE by the Roman Emperor Constantine that made Christianity an accepted religion is A. The Edict of Milan. This historic proclamation effectively ended any state-sanctioned persecution of Christians within the Roman Empire and allowed citizens to worship any deity they wished, thereby legalizing Christianity.
Constantine's edict allowed for the confiscated property of Christians to be returned and for their legal rights to be reinstated. Although it did not make Christianity the official religion of Rome at that time, the Edict of Milan was a significant step in Christianity's path to becoming the dominant religion in the empire.
The document issued in 313 CE by the Roman Emperor Constantine that made Christianity an accepted religion is The Edict of Milan.
This edict allowed citizens to worship any deity they wished and ended the state-sanctioned persecution of Christians within the Roman Empire. It did not make Christianity the official state religion, but it granted religious toleration and restored property and legal rights to Christians.