Would an Antibody Response Against the B Subunit of an A-B

Multiple Choice

Would an antibody response against the B subunit of an A-B toxin protect against the effects of the toxin?

A) Yes. If antibodies bind to the B portion, the toxin can no longer bind to target cells and will thus not affect those cells.
B) No. Even if antibodies bind to the B portion of the toxin, it is the A portion that actually causes damage to the cell.
C) Yes. If antibodies bind to the B portion, that portion of the toxin does not become activated, and thus does not damage the host cell.
D) No. Even if antibodies bind to the B portion of the toxin, the toxin is still taken into the host cell by phagocytosis, damaging that cell.
E) This question cannot be answered. The immune system does not mount a strong response against proteins, so this situation is unlikely to occur.