The correct answer is B: Plantations grew larger after the Civil War as land was available.
After the Civil War, many plantations that were previously worked by enslaved people saw changes in ownership and operation. Some land was available due to the abolition of slavery, and larger plantations could develop as smaller farms were consolidated or as former plantation owners sought to maintain their production levels. Sharecropping also emerged, but many farms did become larger in the post-war South, as former plantation owners adapted to the new labor system.