Which sentence does not contain any errors in comma usage?

AA paper mill eventually opened in Spain and, the art of making paper spread from here.

BThe inventor gathered bark and rags and then he or she made a pulp.

CThe Chinese kept the formula to themselves, but, in 751 the Arabs learned the Chinese secret.

DSome papermakers used rags, and others used animal hides.

I will give a Brainliest answer and you can my best sister or brother.