This question relates to Mendel's breeding experiments with peas. A true breeding plant producing smooth peas was crossed with a true-breeding plant producing wrinkled peas (cross 1). The offspring of cross 1 all produced smooth peas. The offspring of cross 1 were then crossed with the wrinkled-pea parent (cross 2). Which of the statements about the cross outcomes are true? Please select all that apply.
A) Half the offspring of cross 2 had smooth peas B) All the offspring of cross 2 had smooth peas C) All the offspring of cross 1 had the same genotype D) The offspring of cross 2 had a 3:1 smooth:wrinkled ratio E) The wrinkled allele is recessive