title: List of tallest buildings
context: The international non-profit organization Council on Tall Buildings and Urban Habitat (CTBUH) was formed in 1969 and announces the title of "The World's Tallest Building" and sets the standards by which buildings are measured. It maintains a list of the 100 tallest completed buildings in the world.[3] The organization currently ranks Burj Khalifa in Dubai as the tallest at 828m (2,717ft).[3] The CTBUH only recognizes buildings that are complete however, and some buildings included within the lists in this article are not considered finished by the CTBUH.
question: What is the worlds tallest building?
answers: Burj Khalifa