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: Hello. 
 agent: Hello. How can I help you today? 
 customer: I want to cancel my recent reservation owing to an emergency. 
 agent: Sure, I am here to help you with that. Can you please tell me your name? 
 customer: My name is Dennis Wilson. 
 agent: Here, I found your reservation and it is successfully cancelled. 
 customer: Thank you. 
 agent: Thank you for opting us, have a nice day.
A:
cancel