Unattached Earlobes (EE or Ee)are Dominant Over Attached Earlobes (Ee)

Multiple Choice

Unattached earlobes (EE or Ee) are dominant over attached earlobes (ee) .A couple both have unattached earlobes.Both notice that one of their parents on both sides have attached earlobes (ee) .Therefore,they correctly assume that they are carriers for attached earlobes (Ee) .If the couple proceeds to have four children,then

A) they can be certain that three will be heterozygous and one homozygous recessive.
B) if the first three are heterozygous,the fourth must be homozygous recessive.
C) the children must repeat the grandparents' genotype (Ee) .
D) all children must have unattached earlobes since both parents possess the dominant gene for it.
E) two heterozygous,one homozygous dominant,and one homozygous recessive is a likely outcome,but all genotype ratios are possible.