Which of the following statements about antibody affinity maturation is true?

• A. It is a form of natural selection ensuring only antibodies that most effectively bind the antigen are produced.
• B. It occurs when mutations happen in the DNA encoding the variable region of the antibody.
• C. It ensures that only B cells with BCRs that effectively bind the antigen are allowed to proliferate.
• D. After an affinity maturation cycle, the majority of the B cell population will create antibodies that bind the antigen.
• E. A and B.
• F. B and C.
• G. All of the above are true about affinity maturation.