All characters of palatine tonsil except

Correct Answer: D

Rationale: Palatine tonsils have non-keratinized epithelium , glands opening into crypts , and nodules ; they are non-capsulated but prone to inflammation (D is incorrect).

Correct Answer: D

Rationale: Macrophages are part of innate immunity; T cells , antibodies , and B cells are components of adaptive immunity.

Correct Answer: A

Rationale: NK cells produce cytokines and release cytotoxic chemicals ; they detect missing MHC I (C indirectly), not general traits , and activate macrophages secondarily.

Correct Answer: C

Rationale: B7 binds CD28 for T-cell co-stimulation ; not TCR-nucleus , adhesion , or upregulation .

Correct Answer: C

Rationale: Mucus acts as a barrier with antimicrobial proteins ; protection is broader, SCFAs are microbiota-derived, not nutrient transport .