Q: 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
customer: Hi. I am Donald Williams. 
 agent: Hello. How can I assist you? 
 customer:  I want to go for an industrial tour conducting by our college management, can you please book me a ticket from DEN to ATL? 
 agent: Sure, may I know your journey dates please? 
 customer: My travelling dates are 12/26 to 12/28. 
 agent: Delta airlines is having a flight with travel charge of 200, shall I proceed booking? 
 customer: You can book it. 
 agent: Your ticket has been booked with flight-1022, have a safe journey. 
 customer: Thank you for helping. 
 agent: It's ok, thank you for choosing us.
A:
book