Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Mollusks live in most terrestrial, freshwater, and marine habitats. However, the majority of species live in the ocean. They can be found in both shallow and deep water and from tropical to polar latitudes. They have a variety of ways of getting food. Some are free-living heterotrophs. Others are internal parasites. Mollusks are also eaten by many other organisms, including humans. Answer: ocean

Answer: Where do the majority of species live?

Question: Passage: The first period of the Paleozoic Era was the Cambrian. By the beginning of the Paleozoic, organisms evolved shells. Shells could hold their soft tissues together. Shells could protect them from predators and from drying out. Some organisms evolved external skeletons. These are called exoskeletons . Organisms with hard parts also make good fossils. Fossils from the Cambrian are much more abundant than fossils from the Precambrian. Answer: cambrian

Answer: The first period of the paleozoic era was called what?

Question: Passage: The simple carbohydrates discussed above are used as the building blocks for complex carbohydrates. Monosaccharides like glucose or fructose can be linked together to form larger structures. When two monosaccharides are bound together, the result is a disaccharide . Some common disaccharides are shown in the Table below . Answer: disaccharide

Answer:
What is the result when two monosaccharides are bound together?