Final answer:
Since the 1990s, China has significantly reformed its economy from a command system to a more market-oriented approach, marked by the introduction of private enterprise, international trade, and economic zones that have boosted growth and improved the standard of living.
Step-by-step explanation:
The changes in China's economy since the 1990s have been significant and multifaceted. Since the 1980s, and more expansively in the 1990s, China began to shift away from a purely command economy towards a more market-oriented economy. This shift was characterized by the introduction of market reforms that allowed for private enterprise and international trade to flourish. The economic policies of leader Deng Xiaoping, especially the 'Four Modernizations', played a critical role in transforming China's economy by encouraging entrepreneurship and foreign investment. Moreover, China's entry into the World Trade Organization (WTO) in 2001 has further integrated it into the global economy, accelerating its rise as a major economic power.
These economic reforms have not only increased China's international investment but also resulted in the establishment of Special Economic Zones (SEZs) that boosted urban and manufacturing growth, particularly in coastal cities. Consequently, this has led to a tremendous rural-to-urban shift in the population as well as significant improvements in the standard of living for a large portion of China's population. Thus, the most accurate statement regarding the changes in China's economy since the 1990s is A) China's shift to greater market economy reforms.