A term generally used to describe all white blood cells is:

Correct Answer: D

Rationale: Leukocytes is the general term for all white blood cells, unlike specific progenitors or cell types.

Correct Answer: D

Rationale: Antigens have multiple epitopes ; receptors (A, B) bind them.

Correct Answer: D

Rationale: Fluid flows from blood capillaries to interstitial spaces, into lymphatic capillaries, then vessels, ducts, and finally subclavian veins.

Correct Answer: D

Rationale: Antibody production is specific (adaptive), unlike phagocytosis or inflammation (nonspecific).

Correct Answer: C

Rationale: Vaccines stimulate a primary immune response, generating memory cells.