Both B and T cells are originally derived from cells of the:

A. IgD: Immunoglobulin D (IgD) is found on the surface of B cells and serves as a receptor for antigen recognition during the immune response. Its exact function is not fully understood, but it plays a role in the activation of B cells.

B. IgE: Immunoglobulin E (IgE) is primarily associated with allergic responses and defense against parasitic infections. When an allergen enters the body, IgE antibodies trigger the release of histamine and other chemicals, leading to allergy symptoms. IgE is also involved in protecting against certain parasites.

C. IgG: Immunoglobulin G (IgG) is the most abundant immunoglobulin in the bloodstream. It provides long-term immunity by recognizing and neutralizing pathogens such as bacteria and viruses. IgG antibodies are involved in secondary immune responses and are transferred from mother to fetus, providing passive immunity.

D. IgM: Immunoglobulin M (IgM) is the first antibody produced during an initial immune response to an antigen. It is effective at agglutination (clumping) of pathogens. IgM antibodies are generally found in blood and lymph fluid and are the first line of defense during infections.

A. "The antibiotic I have been taking doesn't work as well as it used to."
This statement shows awareness of decreased effectiveness, which can occur due to drug resistance. Bacteria can become resistant to antibiotics, leading to reduced efficacy of the medication over time.

B. "The bacteria in my body have become resilient."
This statement correctly attributes resistance to the bacteria. Resilience in this context means that bacteria have developed mechanisms to survive the effects of antibiotics, making the treatment less effective.

C. "Over time, an organism that had once been highly sensitive to an antibiotic may become less susceptible, or it may lose drug sensitivity entirely."
This statement accurately describes the concept of drug resistance. Bacteria can lose sensitivity to antibiotics, rendering the drugs ineffective against them.

D. "My body has become resistant to the antibiotic."
This statement is incorrect. It's the bacteria that develop resistance, not the patient's body. Patients don't become resistant to antibiotics; instead, bacteria evolve and adapt, making the drugs less effective against them.