The Church of Christ sounds like a pretty reasonable answer to me. Jesus Christ said He was going to build His Church, and He did. I don't know that it went by that name, but it was quite a few years before there was a Roman Catholic Church, and those of us who are not Catholic are not convinced that the Church known as the Catholic Church today is the same Church Jesus Christ established. The post-apostolic Church was incredibly splintered. There were dozens of different "denominations," if you will, by as early as the end of the first century. While it is true that one of them became dominent and took on the designation of "catholic," that in and of itself does not mean that it was the "original" Church. (The "original" one believed in "Mom," by the way.
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