Why did the us formulate the open door policy toward china? question 3 options: to develop democratic institutions and practices in china to establish a military presence on the chinese mainland to support japanese efforts to industrialize china to prevent a european and japanese monopoly of chinese trade and markets

The answer is To prevent a European and Japanese monopoly of Chinese trade and markets.

Explanation:

As the European colonial powers and the imperial Japan made significant territorial, economic and military gains in the chinese mainland, USA, who was looking to expand their nation both in terms of territory and economically understood the massive economic potential in China.

they were all fought in the middle east during ww1