Final answer:
The most significant effect of woodblock printing in China during the Middle Ages was the c. preservation and dissemination of knowledge, which led to increased literacy and spread of cultural and intellectual insights.
Step-by-step explanation:
The effect of woodblock printing in China during the Middle Ages was most significantly related to the preservation and spread of knowledge. This innovation democratized access to texts by enabling their mass production, which in turn supported widespread education and literacy. The Song Dynasty greatly benefited from woodblock printing as it allowed for the printing of Confucian and Buddhist texts, educational materials, political pamphlets, and even currency. This technology facilitated cultural and intellectual advances by making information more accessible to a broader segment of society.