Read this and answer the question. If the question is unanswerable, say "unanswerable".

Metropolitan Kathmandu is divided into five sectors: the Central Sector, the East Sector, the North Sector, the City Core and the West Sector. For civic administration, the city is further divided into 35 administrative wards. The Council administers the Metropolitan area of Kathmandu city through its 177 elected representatives and 20 nominated members. It holds biannual meetings to review, process and approve the annual budget and make major policy decisions. The ward's profile documents for the 35 wards prepared by the Kathmandu Metropolitan Council is detailed and provides information for each ward on population, the structure and condition of houses, the type of roads, educational, health and financial institutions, entertainment facilities, parking space, security provisions, etc. It also includes lists of development projects completed, on-going and planned, along with informative data about the cultural heritage, festivals, historical sites and the local inhabitants. Ward 16 is the largest, with an area of 437.4 ha; ward 26 is the smallest, with an area of 4 ha.

What sector of Kathmandu doesn't have the word 'sector' in its name?
City Core