Final answer:
The scholar gentry became dominant in Chinese politics and society due to the overthrow of the Tang aristocracy, the development of printing technology, and the possibility of social mobility based on merit and education.
Step-by-step explanation:
The scholar gentry became a dominant force in Chinese politics and society from the early Tang through the Song periods due to several factors:
- The Tang aristocracy, who had previously monopolized office, were killed and dispersed by the Huang Chao rebellion.
- Printing technology was developed and widely used during the Song period, making educational materials and Confucian texts more accessible to a larger portion of the population.
- Social mobility was possible based on merit and education. Hardworking individuals could rise into the gentry elite, while gentry families whose sons neglected education and work could fall back into the working class.