Please answer the following question: Read the following conversation and answer the question. W: Professor Clark said that the mid-term exam would cover the first 15 lessons? M: Really? I thought it only included the first 12 lessons. Then I must spendthe weekend to go over the rest of the lessons. Question: How many lessons must the man review over the weekend? - Five lessons. - Three lessons. - Twelve lessons.
A:
Three lessons.