Two newborns are assessed at 5 minutes of life. Infant A (term, vaginal delivery) has APGAR 8 with pink body, blue extremities, spontaneous cry, and good muscle tone. Infant B (term, vacuum-assisted delivery) has APGAR 6 with pale body, cyanosis, weak cry, and decreased muscle tone. Which single feature best discriminates the clinical urgency and risk of adverse outcome between these two infants?