Question

When Mendel crossed a plant with green peas and a plant with yellow peas, what color peas did the offspring have?

All offspring had green peas.
All offspring had yellow peas.
Half of the offspring had yellow peas and half had green peas.
Some of the offspring had yellow peas and some had yellow-green peas.

Answer 1

All offspring had yellow peas.
Yellow is the dominant trait, so a cross of true-breeding yellow (YY) × green (yy) gives all Yy offspring that show the yellow phenotype.