A 24-year-old runner sustains a concussion during a football match with brief loss of consciousness. CT head is normal. According to concussion/mild traumatic brain injury guidelines, which advice regarding return to play is most appropriate?AReturn to full contact sport the next day if symptoms are mildBFollow a graded return-to-play protocol, progressing only when symptom-free at each stageCAvoid any physical activity for 6 monthsDReturn to full work and sport immediately because imaging is normalEDriving and sport restrictions are unnecessary once headaches improve slightlyCheck my answer