Question: Which is a provincial capital, Zhengzhou or Huangzhou District?

Context paragraphs:
Rolea B'ier District: Rolea B'ier District (Khmer: ស្រុករលាប្អៀរ ) is a district ("srok") in the center of Kampong Chhnang Province, in central Cambodia.  The district capital is Rolea B'ier, a town located 5 kilometres south of the provincial capital of Kampong Chhnang.  The district is surrounded by other Kampong Chhnang districts and in turn surrounds Kampong Chhnang District which includes the provincial capital.  The Tonle Sap serves as the border of the district in the north east.  The Kampong Chhnang Airport, built during the period of Democratic Kampuchea (the regime of the Khmer Rouge) lies in Krang Leav commune.

Xian (state): Xian () was a minor state of the Western Zhou and Spring and Autumn periods, whose capital was located at modern-day Qishui, Huangzhou District.  While it controlled only a small territory along the Yangtze, the Wei clan (隗) that ruled Xian maintained far-reaching diplomatic and marital relations with many neighboring states.

Huang Prefecture: Huangzhou or Huang Prefecture was a "zhou" (prefecture) in imperial China, centering on modern Huangzhou District, Huanggang, Hubei, China.  It existed (intermittently) from 585 until 1279.

Luoyang: Luoyang, formerly romanized as Loyang, is a city located in the confluence area of Luo River and Yellow River in Central China.  It is a prefecture-level city in western Henan province.  It borders the provincial capital of Zhengzhou to the east, Pingdingshan to the southeast, Nanyang to the south, Sanmenxia to the west, Jiyuan to the north, and Jiaozuo to the northeast.  As of the final 2010 census, Luoyang had a population of 6,549,941 inhabitants with 1,857,003 people living in the built-up ("or metro") area made of the city's five urban districts, all of which except the Jili District are not urbanized yet.

Mmabatho: Mmabatho (Setswana for "Mother of the People") is the former capital of the North-West Province of South Africa.  In the apartheid era, it was the capital of the former "Bantustan" of Bophuthatswana.  Following the end of apartheid in 1994, Bophuthatswana was integrated into the newly established North-West Province and Mmabatho was proclaimed the provincial capital.  However, Mmabatho status as the provincial capital was short-lived.  Later in 1994, the North West provincial legislature voted to rename the capital to Mafikeng (the town of Mafikeng having been merged with Mmabatho in 1980 and treated as a suburb of Mmabatho between 1980 and 1994 ), reducing Mmabatho to a suburb of Mafikeng.

National Highway 5 (Cambodia): National Highway 5 or National Road No.5 (10005) is one of the national highways of Cambodia.  With a length of 407.45 km , it connects the capital of Phnom Penh with Thailand.  NH5 leaves Phnom Penh in a north to northwest direction, it first borders the Tonle Sap, three bridges the Chroy Changvar, the Prek Kdam and the Prek Pnov link the Est of the country.  Then it moves away from the river/lake because the land there is flooded part of the year and it exits Kandal Province and traverses Kampong Chhnang Province from the junction with Road 51, north to Kampong Chhnang City, then northwest to Baribour District where it crosses into Pursat Province.  From there, it skirts the Tonle Sap lake and continues west to Pursat town, the provincial capital.  Leaving Pursat, NH5 again turns northwest and leads to Battambang Province, passing through another provincial capital at Battambang city and continuing on to Serei Saophoan District in Banteay Meanchey Province where it meets the terminus of NH6 and bends westward towards its own terminus at Poipet on the Thai border.

Zhengzhou: Zhengzhou is a Chinese city and the provincial capital of Henan Province in east-central China.  As a prefecture-level city, it also serves as the political, economic, technological, and educational centre of the province, as well as a major transportation hub for Central China.  The city lies on the southern bank of the Yellow River, and is one of the Eight Great Ancient Capitals of China.

Bangkinang: Bangkinang (Jawi: بغكينغ‎ ), is the town near Pekanbaru.  Bangkinang is the capital of Kampar Regency, Riau, which is 60 km from Pekanbaru (Riau provincial capital).  As the capital of the district adjacent to the provincial capital and a connection to the area of West Sumatra.

Huangzhou District: Huangzhou District () is a district of the city of Huanggang, Hubei province, People's Republic of China.

Kampong Siem District: Kampong Siem District (Khmer: ស្រុកកំពង់សៀម "Port of Siam") is a district ("srok") located in Kampong Cham Province, Cambodia.  The district surrounds the provincial capital Kampong Cham City.  The administrative center of the district locates not far from the Provincial capital of Kampong Cham in Ampil Leu Village, Ampil Commune about 3 km west from the center of Kampong Cham city on National Highway 7 and is 120 kilometres by road from Phnom Penh.  The district borders on the western bank of the Mekong for most of its length.

Supporting paragraphs: Zhengzhou Huangzhou District
Answer: Zhengzhou