SAT US History Practice Question

The mechanical reaper, invented by Cyrus McCormick in the 1830s, was most significant because it

1. A.turned over the hard prairie soil.
2. B.planted seeds four times as fast as a man could do by hand.
3. C.aided irrigation of the arid Midwest.
4. D.increased cotton production.
5. E.cut wheat at a greater rate than the scythe.