In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Q: Why do birds possess gizzards?, Context: Like the reptiles, birds are primarily uricotelic, that is, their kidneys extract nitrogenous waste from their bloodstream and excrete it as uric acid instead of urea or ammonia through the ureters into the intestine. Birds do not have a urinary bladder or external urethral opening and (with exception of the ostrich) uric acid is excreted along with feces as a semisolid waste. However, birds such as hummingbirds can be facultatively ammonotelic, excreting most of the nitrogenous wastes as ammonia. They also excrete creatine, rather than creatinine like mammals. This material, as well as the output of the intestines, emerges from the bird's cloaca. The cloaca is a multi-purpose opening: waste is expelled through it, most birds mate by joining cloaca, and females lay eggs from it. In addition, many species of birds regurgitate pellets. Males within Palaeognathae (with the exception of the kiwis), the Anseriformes (with the exception of screamers), and in rudimentary forms in Galliformes (but fully developed in Cracidae) possess a penis, which is never present in Neoaves. The length is thought to be related to sperm competition. When not copulating, it is hidden within the proctodeum compartment within the cloaca, just inside the vent. The digestive system of birds is unique, with a crop for storage and a gizzard that contains swallowed stones for grinding food to compensate for the lack of teeth. Most birds are highly adapted for rapid digestion to aid with flight. Some migratory birds have adapted to use protein from many parts of their bodies, including protein from the intestines, as additional energy during migration.

A: contains swallowed stones for grinding food to compensate for the lack of teeth
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Q: Whose submarines, between the Germans and Soviets, were the Bermuda bases first used to look out for?, Context: Construction began in 1941 of two airbases consisting of 5.8 km2 (2.2 sq mi) of land, largely reclaimed from the sea. For many years, Bermuda's bases were used by US Air Force transport and refuelling aircraft and by US Navy aircraft patrolling the Atlantic for enemy submarines, first German and, later, Soviet. The principal installation, Kindley Air Force Base on the eastern coast, was transferred to the US Navy in 1970 and redesignated Naval Air Station Bermuda. As a naval air station, the base continued to host both transient and deployed USN and USAF aircraft, as well as transitioning or deployed Royal Air Force and Canadian Forces aircraft.

A: German
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Q: How many institutions are there?, Context: Three community college districts exist with campuses in and around Houston. The Houston Community College System serves most of Houston. The northwestern through northeastern parts of the city are served by various campuses of the Lone Star College System, while the southeastern portion of Houston is served by San Jacinto College, and a northeastern portion is served by Lee College. The Houston Community College and Lone Star College systems are within the 10 largest institutions of higher learning in the United States.

A:
Three community college districts
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