Among the options provided, which accurately describes the role of antibodies in the immune response? a) Antibodies are produced by B cells and directly kill pathogens by lysing their cell membranes. b) Antibodies are proteins that bind to specific antigens on pathogens, marking them for destruction by phagocytic cells or activating the complement system. c) Antibodies are small molecules that neutralize toxins released by pathogens, preventing them from causing harm to the host. d) Antibodies are enzymes that catalyze the breakdown of pathogens into harmless byproducts.