China's food problem still depends on itself, which is determined by China's national conditions as a country with a large population. Food prices are the objective result of the process of market creation. Really make great efforts in agricultural infrastructure and agricultural technological progress, cherish every inch of land, make good use of every factor input, and maintain a stable increase in food production and a suitable level of food self-sufficiency. On this basis, it is possible to have " Regardless of the wind and waves, it is more like a walk in leisure court. ". What does the underlined "this basis" mean? ['Introduce foreign advanced agricultural technology and change agricultural production structure.', 'Increasing the sales price of grain and motivating farmers to grow grain.', 'Improving agricultural production factors to ensure adequate food production.', 'Strengthening macro-controls to prevent food markets from falling into blind misunderstandings.']