Question: Westport Airport, in the district of Wichita, is in the Class C airspace of which neighbouring airport which is the largest and busiest in the state of Kansas?

Context paragraphs:
Wichita Dwight D. Eisenhower National Airport: Wichita Dwight D. Eisenhower National Airport (IATA: ICT, ICAO: KICT, FAA LID: ICT) is a commercial airport located about 7 mi west of downtown Wichita, Kansas, United States.  It is the largest and busiest airport in the state of Kansas.  ICT covers 3,248 acres (1,314 ha).

Westport Airport (Oklahoma): Westport Airport (FAA LID: 4F1) is a town-owned, public-use airport located two nautical miles (4 km) east of the central business district of Westport, a town in Pawnee County, Oklahoma, United States.

Northern California TRACON: Northern California TRACON (NCT) (Terminal Radar Approach Control), or NorCal TRACON for short, is an air traffic control facility that provides safety alerts, separation, and sequencing of air traffic arriving, departing, and transiting the airspace and airports in Northern California.  Located in Rancho Cordova near Sacramento, NCT controls airspace over 19000 square miles, and serves Reno International Airport, Sacramento International Airport, San Jose International Airport, Oakland International Airport, and San Francisco International Airport, plus 19 other smaller airports with air traffic control towers.  NCT is the 3rd busiest TRACON in America.  NorCal TRACON is the step between local control (in an airport's control tower) and Air Route Traffic Control Center (ARTCC), in this case, Oakland Center (ICAO code: ZOA).  San Francisco International Airport is the 2nd largest airport in California and the largest airport serving Northern California.

Carters Beach: Carters Beach is a small town on the West Coast of New Zealand's South Island, located 6 km west of Westport on State Highway 67a.  Carters Beach is the only sheltered sandy beach on the West Coast suitable for swimming.  An 18-hole golf course and Westport airport are nearby.  Recently Carters Beach has made local and national news for the erosion along Rotary Road, which has currently caused the closure of the beachside road and may eventually threaten to close the nearby airport.

Westport Airport (Washington): Westport Airport (FAA LID: 14S) is a city owned, public use airport located one nautical mile (2 km) north of the central business district of Westport, a city in Grays Harbor County, Washington, United States.

VFR-on-top: In United States aviation VFR-on-top is defined as air traffic control authorization for an aircraft operating under instrument flight rules (IFR) to do so in visual meteorological conditions (VMC) at any appropriate visual flight rules (VFR) altitude.  A pilot receiving this authorization must comply with the VFR visibility, distance from cloud criteria, and the minimum IFR altitudes.  The use of this term does not relieve controllers of their responsibility to separate aircraft in Class B and Class C airspace or TRSAs.

Mode C veil: Mode C veil refers to a kind of airspace which currently surrounds all primary Class B airports within the United States.  This airspace extends horizontally to a circle of 30 NM radius centered on the airport, and extends vertically from the surface up to 10,000 feet MSL.  The name refers to the mode of transponder operation which is required within this airspace (i.e., with very limited exceptions, all aircraft operating within this airspace must have an altitude reporting Mode C transponder in operation).  All 37 existing (as of August 2016) Class B airports in the United States, have Mode C veil centered on them.  This was not the case for many years, whereas two Class B airports did not have it (at least "de jure"): Houston Hobby Airport and Miramar Naval Air Station.

List of Class C airports in the United States: Class C is a class of airspace in the United States which follows International Civil Aviation Organization (ICAO) air space designation.  Class C airspace areas are designed to improve aviation safety by reducing the risk of mid-air collisions in the terminal area and enhance the management of air traffic operations therein.

Westport Airport (New Zealand): Westport Airport is an airport in Kawatiri, Westport, New Zealand (IATA: WSZ, ICAO: NZWS) .

Westport Airport (Kansas): Westport Airport (FAA LID: 71K) is a privately owned, public use airport located three nautical miles (6 km) southwest of the central business district of Wichita, a city in Sedgwick County, Kansas, United States—and is in the Class C airspace of neighboring Wichita Dwight D. Eisenhower National Airport.

Supporting paragraphs: Westport Airport (Kansas) Wichita Dwight D. Eisenhower National Airport
Answer: Wichita Dwight D. Eisenhower National Airport