Newborns are highly vulnerable to heat loss and cold stress because of their large body surface area-to-mass ratio, limited subcutaneous fat, immature thermoregulatory mechanisms, and wet state at birth. Cold stress triggers metabolic consequences that can rapidly deteriorate the newborn's condition. NCLEX-PN tests the four mechanisms of heat loss, cold stress consequences, and nursing interventions. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you commit. If the stem names a license or role, reread that line; scope errors are classic trap answers even when the clinical topic is familiar. Run a 60-second scan: breathing work and oxygenation, perfusion and end organs, neuro baseline, likely infection sources, and devices that can fail quietly. When two answers feel partly right, pick the one that reduces imminent harm and matches orders for the role you were given. Train yourself to state the primary risk in one short phrase before you read the options so distractors do not rewrite your priority list. On the exam, writers often pair stable-sounding options with unstable data—notice the mismatch before you commit.