Wheat was one of the first plant crops that humans domesticated. In the process of domestication, the wild form of wheat was eventually changed into a form more suited to human agricultural practice. Early farmers most likely used seeds only from wheat plants with —
A.thinner stems that could endure heavy winds
B.larger grains that could produce more food per plant
C.larger flowers that could be sold for additional income
D.taller stems that could block sunlight from weeds growing at ground level