Question: Which airport is located in the state of Maine, Portland International Jetport or Muskegon County Airport?

Context paragraphs:
Mohamed Atta's Nissan: ]A 2001 Nissan Altima, 1N4DL01D81C212547 is the VIN of a blue rental car belonging to Alamo Rent a Car, that was found in the Portland International Jetport parking lot, following the September 11, 2001 attacks.  It was issued a Massachusetts license plate 3335 VI.

Cape Fear Regional Jetport: Cape Fear Regional Jetport (ICAO: KSUT, FAA LID: SUT) , also known as Howie Franklin Field, is a public use airport in Brunswick County, North Carolina, United States.  It is owned by the Brunswick County Airport Commission and located one nautical mile (2 km) northeast of the central business district of Oak Island, North Carolina.  Formerly known as Brunswick County Airport, it is included in the National Plan of Integrated Airport Systems for 2011–2015, which categorized it as a "general aviation" facility.

Muskegon County Airport: Muskegon County Airport (IATA: MKG, ICAO: KMKG, FAA LID: MKG) is a county owned, public use airport in Muskegon County, Michigan, United States.  The airport is located four nautical miles (5 mi, 7 km) south of the central business district of Muskegon, Michigan, in Norton Shores.  It is mostly used for general aviation but is also served by United Express flying CRJ-200 regional jets to its Chicago-O'Hare hub.  The airport and the county of Muskegon restored service to Chicago through the Essential Air Service program.

Twin Cities Air Service: Twin Cities Air Service is an American fixed-base operator and charter airline based at Auburn, Maine and operating from Auburn/Lewiston Municipal Airport and the Portland International Jetport.  The airline is a certified Part 135 operator, providing on demand and commuter service, while the FBO provides standard aircraft services and maintenance, specializing in overhauls of the Cessna 400 series aircraft.  Beginning in March 2010, Twin Cities Air Service began a scheduled commuter route between Portland, Maine, and Yarmouth, Nova Scotia.  At the time of the initiation of this route, Twin Cities was the only scheduled carrier into the Yarmouth Airport, and was the only scheduled international service into the Portland International Jetport.

Muskegon State Park: Muskegon State Park is a 1233 acre state park along Lake Michigan and Muskegon Lake near North Muskegon, Michigan in Muskegon County, Michigan.  The park, located four miles (6 km) west of North Muskegon, has two miles (3 km) of sand beach on Lake Michigan and one mile (1.6 km) on Muskegon Lake.

Muskegon Lake: Muskegon Lake is a 4150 acre fresh-water lake in Muskegon County, Michigan, USA.  Located in the lower peninsula at the mouth of the Muskegon River, Muskegon Lake forms a 12 sqmi broad harbor along the eastern shoreline of Lake Michigan, approximately 2.5 mi wide by 5.5 mi long.

North Muskegon Public Schools: North Muskegon Public Schools is a public school district located in North Muskegon, Michigan.  It is a constituent of the Muskegon Area Intermediate School District in Muskegon County.

Portland International Jetport: Portland International Jetport (IATA: PWM, ICAO: KPWM, FAA LID: PWM) is a public airport two miles (3 km) west of downtown Portland, in Cumberland County, Maine.  It is owned and operated by the city of Portland.  A portion of the Jetport's property, including the main runway, is in the neighboring city of South Portland.

Portland International Airport MAX Station: The Portland International Airport station is a light rail station on the MAX Red Line in Portland, Oregon, located at Portland International Airport.  It is the fourth (and final) stop north on the Airport MAX extension.

Portland International Airport: Portland International Airport (IATA: PDX, ICAO: KPDX, FAA LID: PDX) is a joint civil-military airport and the largest airport in the U.S. state of Oregon, accounting for 90 percent of passenger travel and more than 95 percent of air cargo of the state.  It is located within Portland's city limits just south of the Columbia River in Multnomah County, 6 mi by air and 12 mi by highway northeast of Downtown Portland.  Portland International Airport is often referred to by its IATA airport code, PDX.

Supporting paragraphs: Portland International Jetport Muskegon County Airport
Answer: Portland International Jetport