Question: Aukštaitian, is one of the dialects of the Lithuanian language, spoken in ethnographic regions of Aukštaitija, Dzūkija and which of the smallest of the five cultural regions of Lithuania?

Context paragraphs:
Dzūkian dialect: Dzūkian dialect, known in academic works as Southern Aukštaitian dialect, is one of the three main sub-dialects of the Aukštaitian dialect of Lithuanian language.  Dzūkian dialect is spoken in Dzūkija, southern Lithuania.  Its most distinctive feature is replacing "t", "d" before "i", "į", "y", "ie" and "č", "dž" with "c" and "dz" ("cik" instead of "tik" – just, "dzidumas" instead of "didumas" – size, "pync" instead of "pinti" – to braid, "sveciai" instead of "svečiai" – guests).  Since the region borders Slavic lands, the dialect has many Slavic loanwords and barbarisms.

Suvalkija: Suvalkija or Sudovia (Lithuanian: "Sūduva" or "Suvalkija" or "Užnemunė" ) is the smallest of the five cultural regions of Lithuania.  Its unofficial capital is Marijampolė.  People from Suvalkija are called "suvalkiečiai" (plural) or "suvalkietis" (singular).  It is located south of the Neman River, in the former territory of Vilkaviškis bishopric.  Historically, it is the newest ethnographic region as its most distinct characteristics and separate identity formed during the 19th century when the territory was part of Congress Poland.  It was never a separate political entity and even today it has no official status in the administrative division of Lithuania.  However, it continues to be the subject of studies focusing on Lithuanian folk culture of the 19th and early 20th centuries.

Aukštaitija: Aukštaitija (] , "Highlands") is the name of one of five ethnographic regions of Lithuania.  The name comes from the relatively high elevation of the region, particularly the eastern parts.

Samogitia: Samogitia or Žemaitija (Samogitian: "Žemaitėjė"; Lithuanian: "Žemaitija" ; see below for alternate and historical names) is one of the five ethnographic regions of Lithuania.  Žemaitija is located in northwestern Lithuania.  Its largest city is Šiauliai.  Žemaitija has a long and distinct cultural history, reflected in the existence of the Samogitian dialect.

Aukštaitian dialect: Aukštaitian (Lithuanian: "Aukštaičių tarmė" ) is one of the dialects of the Lithuanian language, spoken in ethnographic regions of Aukštaitija, Dzūkija and Suvalkija.  It became the basis for the standard Lithuanian language.

Regions of Lithuania: Lithuania can be divided into historical and cultural regions (called ethnographic regions).  The exact borders are not fully clear, as the regions are not official political or administrative units.  They are delimited by culture, such as country traditions, traditional lifestyle, songs, tales, etc.  To some extent regions correspond to the zones of Lithuanian language dialects.  This correspondence, however, is by no means strict.  For example, although the Dzūkian dialect is called South Aukštaitian, it does not mean that Dzūkija is part of Aukštaitija.  In certain parts of some regions, dialects of other regions are spoken, while for example in Samogitia, there are three indigenous dialects (southern, northern and western Samogitian), some of which are subdivided into subdialects.

Balkan dialects of Bulgarian: The Balkan dialects are the most extensive group of dialects of the Bulgarian language, covering almost half of the present-day territory of Bulgaria and slightly less than a third of the territory on the Balkans where Bulgarian is spoken.  Their range includes north-central Bulgaria and most of the Bulgarian part of Thrace, excluding the Rhodopes, the region of Haskovo and Strandzha.  As a result of the mass population movements that affected eastern Bulgaria during the 19th and the beginning of the 20th century, the Balkan dialects are now spoken also in vast areas of northeastern Bulgaria, especially the regions of Dobrich and Varna.  The most significant feature of the dialects, as in most Eastern Bulgarian dialects, is the pronunciation of Old Church Slavonic ѣ (yat) as ʲa or ɛ , depending on the character of the following syllable.  The Balkan dialects, and in particular, the Central Balkan dialect, lie at the foundation of formal Bulgarian.  However, they are not identical to the standard language because many of its features derive from the Western Bulgarian dialects, including the Macedonian dialects, or are a compromise between Eastern and Western standard.

Dzūkija: Dzūkija or Dainava is one of five ethnographic regions of Lithuania.  Dzūkija is a cultural region defined by traditional lifestyles and dialects of the local Lithuanian population (mostly rural farmers) and has never been defined as a political or administrative unit.  Traditionally, Alytus is regarded as the capital of the region, although it is not the largest city in Dzūkija (because Vilnius vicinities lost Lithuanian language centuries ago).

Ethnographic Lithuania: Ethnographic Lithuania was an early 20th-century concept that defined Lithuanian territories as a significant part of the territories that belonged to Grand Duchy of Lithuania and Lithuanians as all people living on them, regardless of whether those people spoke Lithuanian language and considered themselves Lithuanian.  The concept was in contrast to those of "historic Lithuania" – the territories of the Duchy – and the "linguistic Lithuania", the area where Lithuanian language was overwhelmingly spoken.

Aukštaitija National Park: Aukštaitija National Park is a national park in north-eastern Lithuania, about 100 km north of Vilnius.  Established in 1974, it is the oldest of the five national parks in Lithuania.  At first it was named Lithuanian SSR National Park to emphasize that it was the first such park in the republic.  In 1991 four other parks were established and were named after ethnographic regions of Lithuania.  The park was renamed after Aukštaitija.

Supporting paragraphs: Aukštaitian dialect Suvalkija
Answer: Suvalkija