Which of the following statements regarding the adaptive immune response is false?

Correct Answer: B

Rationale: Answer B is correct because the major histocompatibility complex (MHC) is indeed required for the activation of T helper cells by a foreign antigen. This is because T helper cells recognize antigens presented by MHC molecules on antigen-presenting cells. Without MHC presentation, T helper cells cannot be activated. Choice A is incorrect because MHC molecules do display both self and non-self antigens, which is crucial for the immune system to distinguish between harmful invaders and healthy cells. Choice C is incorrect because activated effector T helper cells can indeed activate both T and B lymphocytes/cells, playing a key role in coordinating the adaptive immune response. Choice D is incorrect because T cells do not use 'chemical warfare'; instead, they directly attack infected cells, while B cells produce antibodies that target specific antigens. In summary, choice B is false because the MHC is necessary for T helper cell activation, while choices A, C, and D are true statements regarding the adaptive immune response.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.