A 69-year-old man with COPD and ischaemic heart disease is admitted with fever, productive cough, hypotension, and confusion. NEWS2 score is 9. According to NEWS2-based escalation protocols, what is the most appropriate response?AReview in 4 hours and repeat observationsBInform the nurse in charge but take no immediate actionCUrgent review by a senior clinician and consider critical care involvementDDischarge as his COPD explains high scoresEStart oral antibiotics as an outpatientCheck my answer