Suppose both the father and the mother are "heterozygous" for the gene that controls ability to curl the tongue lengthwise, and this gene is dominant. What can we predict about their children?

Suppose both the father and the mother are "heterozygous" for the gene that controls ability to curl the tongue lengthwise, and this gene is dominant. What can we predict about their children?

a. All will be heterozygous for the ability to curl.
b. All will be homozygous for the ability to curl.
c. All will be homozygous for the inability to curl.
d. They may be homozygous or heterozygous for ability to curl, or homozygous for inability.