This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[Q]: Passage: Galicia has a surface area of 29,574 square kilometres (11,419 sq mi). Its northernmost point, at 4347N, is Estaca de Bares (also the northernmost point of Spain); its southernmost, at 4149N, is on the Portuguese border in the Baixa Limia-Serra do Xures Natural Park. The easternmost longitude is at 642W on the border between the province of Ourense and the Castilian-Leonese province of Zamora) its westernmost at 918W, reached in two places: the A Nave Cape in Fisterra (also known as Finisterre), and Cape Tourinan, both in the province of A Coruna. Question: And its southernmost?
[A]: Baixa Limia-Serra do Xures

[Q]: Passage: In practice, because of sovereignty, any state can withdraw from any treaty at any time. The question of whether this is permitted is really a question of how other states will react to the withdrawal; for instance, another state might impose sanctions or go to war over a treaty violation. Question: What might a state do in response to another state's withdrawal from a treaty?
[A]: impose sanctions or go to war

[Q]: Passage: The ability of birds to return to precise locations across vast distances has been known for some time; in an experiment conducted in the 1950s a Manx shearwater released in Boston returned to its colony in Skomer, Wales, within 13 days, a distance of 5,150 km (3,200 mi). Birds navigate during migration using a variety of methods. For diurnal migrants, the sun is used to navigate by day, and a stellar compass is used at night. Birds that use the sun compensate for the changing position of the sun during the day by the use of an internal clock. Orientation with the stellar compass depends on the position of the constellations surrounding Polaris. These are backed up in some species by their ability to sense the Earth's geomagnetism through specialised photoreceptors. Question: What do birds to compensate for the changing position of the sun during the day?
[A]:
internal clock