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.
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Question: Passage: Phycobilins are a third group of pigments found in cyanobacteria, and glaucophyte, red algal, and cryptophyte chloroplasts. Phycobilins come in all colors, though phycoerytherin is one of the pigments that makes many red algae red. Phycobilins often organize into relatively large protein complexes about 40 nanometers across called phycobilisomes. Like photosystem I and ATP synthase, phycobilisomes jut into the stroma, preventing thylakoid stacking in red algal chloroplasts. Cryptophyte chloroplasts and some cyanobacteria don't have their phycobilin pigments organized into phycobilisomes, and keep them in their thylakoid space instead. Question: What color is phycoerytherin?

Answer: red

Question: Passage: In 1972, the Presbyterian Church of England (PCofE) united with the Congregational Church in England and Wales to form the United Reformed Church (URC). Among the congregations the PCofE brought to the URC were Tunley (Lancashire), Aston Tirrold (Oxfordshire) and John Knox Presbyterian Church, Stepney, London (now part of Stepney Meeting House URC) these are among the sole survivors today of the English Presbyterian churches of the 17th century. The URC also has a presence in Scotland, mostly of former Congregationalist Churches. Two former Presbyterian congregations, St Columba's, Cambridge (founded in 1879), and St Columba's, Oxford (founded as a chaplaincy by the PCofE and the Church of Scotland in 1908 and as a congregation of the PCofE in 1929), continue as congregations of the URC and university chaplaincies of the Church of Scotland. Question: What are the two former Presbyterian congregations in England?

Answer: St Columba's, Cambridge (founded in 1879), and St Columba's, Oxford

Question: Passage: Articles 4653 of the Vienna Convention on the Law of Treaties set out the only ways that treaties can be invalidatedconsidered unenforceable and void under international law. A treaty will be invalidated due to either the circumstances by which a state party joined the treaty, or due to the content of the treaty itself. Invalidation is separate from withdrawal, suspension, or termination (addressed above), which all involve an alteration in the consent of the parties of a previously valid treaty rather than the invalidation of that consent in the first place. Question: Which processes simply alter the consent given by parties to a previously valid treaty rather than invalidating the consent completely?

Answer:
withdrawal, suspension, or termination