Which one of the following statements best describes the role of B cells and T cells in the human body ?

Identifies T cells (helper T cells) as a class of white blood cells critical to the immune system.

A student could combine this with basic knowledge that immune cells can regulate inflammatory responses to ask whether helper T cells influence inflammation and thus pain.

States the immune system protects against infection and that failure leads to disease.

One can extend this to investigate whether immune components (like B and T cells) also modulate inflammatory processes associated with infection and symptoms such as pain.

Defines pain as a symptom indicating something inside us is not working as it should and links symptoms/signs (e.g., swelling) to being unwell.

Use the fact that inflammation and swelling are linked to pain to test whether immune-cell actions that change inflammation would alter pain.

Explains that stimulated cells can release chemical compounds that diffuse and affect other cells, acting as signalling mechanisms.

A student could extend this by checking whether B and T cells release signalling molecules (cytokines) that alter inflammation and pain pathways.

Gives an example (diclofenac, an NSAID) of a drug that reduces inflammation and pain, illustrating that lowering inflammation can reduce pain.

Compare this pharmacological route to biological regulation: if immune cells influence inflammation, then their activity might increase or decrease pain similar to anti-inflammatory drugs.

Identifies helper T cells as a class of white blood cells critical to the immune system and a main cellular target of HIV.

A student could use this to infer that T cells play central immune roles (supporting immune responses) and thus are more likely immune-effectors/regulators than generalized suppressants; checking immunology sources would test whether any T-cell subsets are suppressive.

Explains that vaccines instruct our own body cells—i.e., the immune system can be activated by exposing it to antigens.

One could extend this to reason that B cells and T cells are components that get activated by vaccines (implying immune activation rather than suppression) and then verify which cells are activated.

States that if the immune system fails to protect us we fall ill, and doctors use antibiotics for bacterial infections—distinguishing therapeutic agents from immune cells.

This supports the pattern that medicines (like antibiotics) are called treatments, whereas the immune system itself defends; a student could therefore treat the claim that B/T cells are 'immunosuppressants' with caution and look for specialised cells or drugs that suppress immunity.

Notes that multicellular organisms have specialised cell types that carry out specialised functions and cooperate for survival.

A student could use this general rule to seek whether any specialised lymphocyte subtypes (within B or T cells) have suppressive functions, rather than assuming all B/T cells are immunosuppressive.

Describes how chemical signals (hormones) produced by cells can regulate other cells, illustrating that cell-to-cell regulation is possible via signalling molecules.

This suggests a route to investigate whether some lymphocytes produce suppressive signals (cytokines) that downregulate immunity—prompting targeted lookup of regulatory T cells and suppressive cytokines.

States that our immune system helps protect us from harmful pathogens, establishing a general role for immune components in defence.

A student could infer that specific immune cell types (like B and T cells) are plausible actors in this protective role and then check sources that list immune cell functions.

Explains acquired immunity and that vaccines train the immune system to recognise and attack harmful germs.

Use the idea that vaccination trains particular immune cells to recognise pathogens to hypothesize which cell types (B/T cells) mediate recognition and long-term protection.

Names helper T cells as a class of white blood cells critical to the immune system and notes that HIV targets them, implying their importance in defence.

From the importance of helper T cells one could infer T cells contribute to protection against infections and seek specifics on their protective functions versus pathogens.

Gives an example (tetanus shot) where the immune system learns to fight a bacterial toxin without causing disease, illustrating immune memory and targeted responses.

A student can extend this to consider which immune cells form memory and produce targeted responses after vaccination (suggesting roles for B cells and T cells).

Distinguishes antibiotics (acting on bacteria) from the immune system implication that other infections (viruses, protozoa) require different defence — i.e., the body's immune mechanisms are key for non-bacterial pathogens.

This contrast supports investigating which immune cells (B and T cells) handle pathogens that antibiotics do not, such as viruses.