Final answer:
The United States has a significant role in the global corn market, involved in diverse uses such as biofuels and livestock feed, with its exact contribution to world corn production varying over time.
Step-by-step explanation:
The United States plays a significant role in global agriculture, particularly when it comes to corn production. Although the exact percentage of the world's total corn production the United States is responsible for can fluctuate year by year, the provided information suggests a substantial contribution. While detailed current percentages are not provided in the reference material available, the U.S. has historically been a major producer of corn, utilizing various policies and market strategies to manage production and pricing.
For instance, the use of corn for biofuels, such as ethanol, and as feed for livestock like cattle, chickens, and hogs illustrates the diverse applications of corn in the U.S. economy. Additionally, changes in crop allocations, as seen in North Dakota's increased corn planting, indicate the dynamic nature of agricultural production based on economic factors, policy decisions, and market demands. It is also noted that field corn is the most common crop in the U.S., highlighting its prominence in the nation's agricultural landscape.