A 23-year-old man is brought to A&E after a witnessed collapse. He is unresponsive and not breathing normally. What is the most appropriate initial step according to adult basic life support guidelines?ACheck carotid pulse for 30 seconds then start chest compressions if absentBDeliver 5 rescue breaths before starting compressionsCCall for help and start chest compressions at 30:2 ratioDPlace him in the recovery position and monitorEAttach a defibrillator only after 5 minutes of CPRCheck my answer