Select the correct answer.

Which sentence best explains how the widespread application of steam power affected English agriculture in the first half of the nineteenth century?

A. The use of steam-powered harvesting machines increased farm output.
B. Agricultural produce could be marketed far from the areas where it was grown.
C. The availability of inexpensive water pumps exhausted groundwater sources in many areas.
D. The migration of labor from rural to urban areas led to a decrease in agricultural output.