Solution:Both (A) and (R) are true but (R) is not the correct explanation of (A).
Since the circulation of the manuscripts started to gradually increase, the need for more scribes rose not only for the rich people but also for the booksellers. The demand for more books increased, as well as the demand for manuscripts. Moreover, copying and producing was not only difficult but also required a lot of skill as well as time. But the demand was rising so quickly that even Chinese woodblock printing was not able to meet the demand. This gave rise to the innovation by Gutenburg, the new printing press. It is also true that the earliest form of paper which was imported into Europe came from China by the Silk Route. As a result, the above-mentioned reason does not support the assertion.