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.

Example Input: Passage: The term alloy is used to describe a mixture of atoms in which the primary constituent is a metal. The primary metal is called the base, the matrix, or the solvent. The secondary constituents are often called solutes. If there is a mixture of only two types of atoms, not counting impurities, such as a copper-nickel alloy, then it is called a binary alloy. If there are three types of atoms forming the mixture, such as iron, nickel and chromium, then it is called a ternary alloy. An alloy with four constituents is a quaternary alloy, while a five-part alloy is termed a quinary alloy. Because the percentage of each constituent can be varied, with any mixture the entire range of possible variations is called a system. In this respect, all of the various forms of an alloy containing only two constituents, like iron and carbon, is called a binary system, while all of the alloy combinations possible with a ternary alloy, such as alloys of iron, carbon and chromium, is called a ternary system. Question: A five-part alloy is known as?
Example Output: ternary alloy

Example Input: Passage: In exchange for Rupert Murdoch's support, Blair agreed not to join the European Exchange Rate Mechanism – which John Major had withdrawn the country from in September 1992 after barely two years. Cabinet Minister Peter Mandelson was "outed" by Matthew Parris (a former Sun columnist) on BBC TV's Newsnight in November 1998. Misjudging public response, The Sun's editor David Yelland demanded to know in a front page editorial whether Britain was governed by a "gay mafia" of a "closed world of men with a mutual self-interest". Three days later the paper apologised in another editorial which said The Sun would never again reveal a person's sexuality unless it could be defended on the grounds of "overwhelming public interest". Question: Who was editor of The Sun in 1998?
Example Output: David Yelland

Example Input: Passage: The Early Cretaceous spans from 145 million to 100 million years ago. The Early Cretaceous saw the expansion of seaways, and as a result, the decline and extinction of sauropods (except in South America). Many coastal shallows were created, and that caused Ichthyosaurs to die out. Mosasaurs evolved to replace them as head of the seas. Some island-hopping dinosaurs, like Eustreptospondylus, evolved to cope with the coastal shallows and small islands of ancient Europe. Other dinosaurs rose up to fill the empty space that the Jurassic-Cretaceous extinction left behind, such as Carcharodontosaurus and Spinosaurus. Of the most successful would be the Iguanodon which spread to every continent. Seasons came back into effect and the poles got seasonally colder, but dinosaurs still inhabited this area like the Leaellynasaura which inhabited the polar forests year-round, and many dinosaurs migrated there during summer like Muttaburrasaurus. Since it was too cold for crocodiles, it was the last stronghold for large amphibians, like Koolasuchus. Pterosaurs got larger as species like Tapejara and Ornithocheirus evolved. Question: What species died out due to the expansion of coastal shallows?
Example Output:
Ichthyosaurs