Final answer:
In the Tang and Song eras, the old landed aristocracy was replaced by the bureaucratic class, consisting of scholar-officials who achieved their status through success in the civil service examinations on Confucian texts and literature.
Step-by-step explanation:
In the Tang and Song eras, the old landed aristocracy was replaced by the bureaucratic class as the political and economic elite of Chinese society. This bureaucratic class, often referred to as scholar-officials, emerged from those who succeeded in the civil service examinations. These exams, which focused on Confucian texts and Chinese literature, were the gateway to becoming a part of the ruling elite, and they made the process more meritocratic. Families of the gentry class had to continually invest in education to maintain their status, and this system lasted until the dynastic system's fall in 1911.
The examination system effectively democratized the bureaucracy, where mandarins or scholar-officials gained power through their knowledge and ability, rather than through inheritance or military prowess. The Song Dynasty in particular is well-known for its reforms which advanced this meritocratic approach. As the Tang and Song Dynasties developed, the class structure of society evolved, and the scholar-officials who passed the civil service exams became the mainstay of Chinese administration, effectively replacing the older hereditary aristocracy as the principal ruling class.