25. A recovered patient is re-exposed to the same virus months later. Which sentence best describes the secondary response?
(A) Rapid activation of memory B cells, leading to high IgG concentrations.
(B) Slower and weaker than the primary response because memory cells suppress immunity.
(C) IgM is always higher than IgG due to lack of class switching.
(D) No antibody response occurs because the virus is cleared by fever alone.
(E) Only innate immunity is involved; adaptive immunity does not respond.