For each question, choose the correct answer (A, B or C). (Chọn câu trả lời đúng cho mỗi câu hỏi (A, B hoặc C)) (1.0 point) If you are not well and miss a class, please ask a classmate to tell you what was taught. From: Flora To: Tony Congratulations, Tony! I heard that you passed maths Have a great birthday. And next time I write to you, you'll be 15. Best wishes, Flora DO NOT ENTER! Staff and business visitors only. No customers past this sign What does this sign mean?