If the CDS-Bond Basis Is X Minus Y,what Are X

Multiple Choice

If the CDS-bond basis is X minus Y,what are X and Y?

A) X is the CDS spread and Y is the excess of the bond yield over the swap rate
B) X is the excess of the bond yield over the swap rate and Y is the CDS spread
C) X is the CDS spread and Y is the excess of the bond yield over the Treasury rate
D) X is the excess of the bond yield over the Treasury rate and Y is the CDS spread