单项选择题

Directions: You are going to hear four conversations. Before listening to each conversation, you will have 5 seconds to read each of the questions which accompany it. After listening, you will have time to answer each question by choosing A, B, C or D. You will hear each conversation ONLY ONCE. Mark your answers in your test booklet. Questions 11 ~ 14 are based on the following conversation. How many persons are in the conversation

A.One.
B.Two.
C.Three.
D.Sour.