Bill Wants to Determine His Blood Type, So He Takes

Bill wants to determine his blood type, so he takes a few drops of blood from a puncture wound in his finger and mixes it with various antisera. His blood cells agglutinate when mixed with the anti-A serum and anti-Rh serum, but not with the anti-B serum. This means

A) Bill could receive type B blood in a transfusion.
B) Bill could donate blood to an individual with type AB blood.
C) Bill is Rh-negative.
D) Bill's plasma would cross-react with type O negative red blood cells.
E) Bill's plasma contains anti-B antibodies.