The best HLA (Human Leucocyte Antigen) match for trans- plants in order to preference is:
A. `"Parent" gt "sibling" gt "twin" gt "unrelated donor"`
B. `"Sibling" gt "twin" gt "parent" gt "unrelated donor"`
C. `"Twin" gt "sibling " gt "parent" gt "unrelated donor"`
D. `"Twin" gt "unrelated donor" gt "parent" gt "sibling"`