A 27-year-old female presents with a severe sore throat, hoarseness, painful swallowing and low-grade fever. On intraoral examination, a large grey membrane is noticed on the oropharynx. Removal of the membrane reveals a bleeding oedematous mucosa. Which of the following is the most likely diagnosis?

• A. Measles
• B. Diphtheria
• C. Meningococcal disease
• D. Scarlet fever
• E. Streptococcal pharyngitis