In this task, you are given a conversation between a flight agent and the customer. You are given 4 options and you need to select the goal of the conversation. It is provided as part of customer's context, which has to be one of the following: `book`: Make a new reservation, `cancel`: Cancel an existing reservation, `no_flight`: No flight found for the customer's preference, `no_reservation`: No reservation / No change / No cancellation was made in the conversation, mostly enquiring details
Q: customer: Hi. 
 agent: Hello, how may I serve you at this moment? 
 customer: Can you please book a flight ticket from DCA to HOU? 
 agent: Sure, can you please share your journey dates? 
 customer: My journey dates are Mar 3rd and Mar 5th. 
 agent: Do you have any connection limit? 
 customer: I am looking for a connecting flight. 
 agent: Are there any more specifications? 
 customer: No. 
 agent: May I know your name please? 
 customer: Charles Hall. 
 agent: We found a Spirit airlines, flight number 1004, and the fare of 300 in economy class. Shall I proceed? 
 customer: Please proceed. 
 agent: Your ticket has been reserved with connecting flight. 
 customer: Thank you. 
 agent: Thank you for approaching us.
A:
book