Paul is primarily responsible for: defining christianity as a new religion, separate from judaism. the adoption of christianity as the official religion of the roman empire. the spread of christianity into africa, asia, and the americas. all of the choices are correct.

The correct option is A

Defining Christianity as a new religion, separate from Judaism.  He articulated strongly that the same practices of Judaism were no longer a defining factor of Christianity. Christians were not expected for example to undergo circumcision and follow the mosaic laws.