Given the question: Information:  - Upolu is an island in Samoa, formed by a massive basaltic shield volcano which rises from the seafloor of the western Pacific Ocean. The island is long, in area, and is the second largest in geographic area as well as with 135,000 people the most populated of the Samoan Islands. Upolu is situated to the southeast of the "big island", Savai'i. The capital Apia is in the middle of the north coast with Faleolo International Airport at the western end of the island. The island has not had any historically recorded eruptions, although three lava flows date back only a few hundred to a few thousand years.  - Savaii is the largest (area 1700 km) and highest (Mt Silisili at 1,858 m) island in Samoa and the Samoa Islands chain. The island is the fifth largest in Polynesia, behind the two main islands of New Zealand and the Hawaiian Islands of Hawaii and Maui.  - The Independent State of Samoa, commonly known as Samoa and, until 1997, known as Western Samoa, is a unitary parliamentary democracy with eleven administrative divisions. The two main islands are Savai'i and Upolu with four smaller islands surrounding the landmasses. The capital city is Apia. The Lapita people discovered and settled the Samoan islands around 3,500 years ago. They developed a unique language and cultural identity.  - Apia is the capital and the largest city of Samoa. From 1900 to 1919, it was the capital of German Samoa. The city is located on the central north coast of Upolu, Samoa's second largest island. Apia is the only "city" in Samoa and falls within the political district ("itml") of Tuamasaga.  - The National Bank of Samoa is a locally owned and private bank in Samoa .    What entity does 'national bank of samoa' has the relation 'headquarters location' with?
The answer is:
apia