Detailed Instructions: In this task, you're given a dialogue between a customer and a flight booking agent with a gap in the conversation. Your job is to find the answer of the previous dialogue. Avoid using irrelevant extra information while creating the answer. The answer should be relevant to the question before the blank. If you fill the blank with a question, it should have an answer from the agent in the given dialogue. Fill the gap marked with underline.
Problem:customer: Hello. 
 agent: Hello, how may I help you? 
 customer: I am looking to book a flight ticket from HOU to DCA. Can you help me for that? 
 agent: Sure, can I know your travelling dates? 
 customer: My travelling dates are Oct 18 and Oct 20. 
 agent: On which name should I reserve the flight ticket? 
 customer: My name is William Gonzalez. 
 agent: Do you have any connection limit? 
 __ 
 agent: Do you have any other specifications? 
 customer: My depart time is evening. 
 agent: Sorry, there are no flights found on given dates. 
 customer: That's ok, thank you for checking. 
 agent: Thank you for reaching us.
Solution:
customer: I prefer to book a single connecting flight.