The answer is: A. 10%
A farm would be considered as 'large' in united states if its size surpass 2000 Acreage. In united states, only around 10% of the farms fulfill this category. And from that 10%, the majority of those farms belong to the same companies who dominated the market for a single product. (for example, McDonalds have their own farm to raise animals that they use for their food products)