Questions 4 to 7 are based on the following conversation. At the end of the conversation, you will be given 20 seconds to answer the question Now, listen to the conversation.

When was the tunnel opened to the public

A．the government has asked the U.N. agency to help contain the disease
B．the government ordered all chickens in the city killed
C．imports of birds from all over the world were suspended
D．over a million chickens have either died from the flu or been culled

A．It was held in Melbourne, Australia.
B．The Olympic Oath was not recited then.
C．There was torch relay in the opening ceremony.
D．The Olympic Flag was flown for the first time.