Pick the Correct Answer Below and Explain Why It Is

Pick the correct answer below and explain why it is correct. Explain why the alternative answers are incorrect.
Many states prohibit intermarriage of persons who are "lunatics" or who are "insane."
a. This policy is sound, because it protects against the birth of genetically inferior children.
b. This policy is sound, because "lunatics" or "insane" persons are, by definition, not able to comprehend the significance of intermarriage.
c. This policy is unsound, because it discriminates against "lunatics" and "insane" persons.
d. This policy is unsound, because there is no clear or realistic standard by which to determine if one is a "lunatic" or "insane."​