听力原文：Coming up at noon is our special report on polluted air spreading through the cit

y. But first, local residents are protesting against the expansion of roads in Leigh National Park. Forestry officials think this will help bring more visitors, but concerned citizens say the construction and the increased traffic will prove harmful to the environment and affect animals badly. The citizens are currently taking part in a rally in front of the Forestry Department building.

What is the main topic of the report？

A．A new attraction for visitors.

B．A proposal to reduce traffic congestion.

C．A construction project planned in a park.

D．A town hall meeting.