Final answer:
Reflex irritability is scored under 'grimace' in the Apgar assessment; it is scored based on the newborn's reaction to stimulation such as a gentle pinch, with scores ranging from 0 to 2.
Step-by-step explanation:
Reflex irritability is one of the five criteria evaluated in the Apgar scoring system, which is a simple assessment administered to an infant immediately after birth. The reflex irritability criterion is represented by the "grimace" response, which is checked by observing the newborn's response to mild stimulation, such as a gentle pinch.
A score of 0 is given if there is no response, a score of 1 for a grimace or feeble cry, and a score of 2 if there's a vigorous cry, cough, or sneeze. Conducted at 1 minute and again at 5 minutes after birth, these scores help to quickly determine whether the newborn may need immediate medical care.