How Is a Deficiency of Protein S Different from Other

How is a deficiency of protein S different from other vitamin K-dependent plasma protein deficiencies?

A) Deficiency may involve abnormality of the protein S antigen.
B) The quantitative distribution of protein S between free and bound forms may contribute to functional deficiency.
C) Deficiency may involve abnormally low levels of protein S.
D) All of the above
E) None of the above