Yes this source and suggest that the Song dynasty was a golden age. One sentence that supports this statement is "To implement these principles, the Song dynasty introduced Civil Service Exam, aiming to hire people for government

based on peoples ability rather than family wealth" This statement shows that The Song Dynasty has showed strategies that aimed to enhance social mobility. Make it into a claim and start with social mobility is

Social mobility is evident in the Song Dynasty, as demonstrated by the introduction of the Civil Service Exam which aimed to hire individuals for government positions based on their ability rather than their family wealth.