From the last paragraph, we know thatA．e-books are now sold together with the paper versio

From the last paragraph, we know that

A．e-books are now sold together with the paper versions.

B．a digital publication usually takes months or years to get to market.

C．the official publications are actually superior to the self-published ones in quality.

D．publishers have hired different editors in different areas.

请帮忙给出正确答案和分析，谢谢！