TASK DEFINITION: Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
PROBLEM: Iron deficiency is the most common nutritional disorder affecting at least one third of world's population. Though anemia is common manifestation of iron deficiency, other effects of iron deficiency on various tissues, organs and systems are usually under recognized. Impaired brain development and cognitive, behavioural and psychomotor impairment are most worrisome manifestations of iron deficiency. Studies have demonstrated that some of these changes occurring during period of brain growth spurt (<2 years age) may be irreversible. Association of iron deficiency with febrile seizures, pica, breath holding spells, restless leg syndrome and thrombosis is increasingly being recognized. Impaired cell-mediated immunity and bactericidal function are generally noted in iron-deficient persons; however, the findings are inconsistent. Despite proven reversible functional immunological defects in vitro studies, a clinically important relationship between states of iron deficiency and susceptibility to infections remains controversial. Studies from malaria endemic regions have reported increased incidence of malaria in association with iron supplementation. These and some other aspects of iron deficiency are reviewed in this article.

SOLUTION: Which deficiency is the cause of restless leg syndrome?

PROBLEM: The overlap between symptoms of PTSD and MDD is substantial. PTSD symptoms arise after a traumatic experience and the trauma is present in all of the diagnostic clusters. In individuals who have experienced a trauma a long time before, it is difficult to establish the exact moment of onset of their symptoms in relation to the trauma suffered. We proposed to raise awareness among operators who may encounter this problem, with the aim of providing them with valuable help in order to achieve a correct differential diagnosis. A sample of subjects suffering from PTSD without comorbidity was assessed to confirm the diagnosis and the severity of post-traumatic symptoms. The Kruskal-Wallis test was used to compare any modifications in the parameters analyzed through the Davidson Trauma Scale with the presence and severity of depressive symptoms as evaluated by the Hamilton-D scale. Half of the PSTD patients recruited showed values of HAM-D > 18, although an active Major Depressive Episode was clinically excluded. Symptom of "numbing", despite being different from the apathy experienced in depression, is identified as a depressive symptom by the HAM-D. Giving prevalence to depressive symptoms may be misleading for diagnosis and may ultimately result in inappropriate treatment.

SOLUTION: Symptoms of which disorder are evaluated with the Davidson Trauma Scale?

PROBLEM: Fossil fuels are made from plants and animals that lived hundreds of millions of years ago. The plants and animals died. Their remains settled onto the ground and at the bottom of the sea. Layer upon layer of organic material was laid down. Eventually, the layers were buried very deeply. They experienced intense heat and pressure. Over millions of years, the organic material turned into fossil fuels. Fossil fuels are compounds of carbon and hydrogen, called hydrocarbons. Hydrocarbons can be solid, liquid, or gas. The solid form is coal. The liquid form is petroleum, or crude oil. The gaseous form is natural gas. Coal is a solid hydrocarbon. Coal is useful as a fuel, especially for generating electricity. Coal forms from dead plants that settled at the bottom of swamps millions of years ago. Water and mud in the swamp kept oxygen away from the plant material. Sand and clay settled on top of the decaying plants. The weight of this material squeezed out the water and some other substances. Over time, the organic material became a carbon-rich rock. This rock is coal. Coal is a black or brownish-black rock that burns easily (Figure 5.3). Most coal is sedimentary rock. The hardest type of coal, anthracite, is a metamorphic rock. That is because it is exposed to higher temperature and pressure as it forms. Coal is mostly carbon, but some other elements can be found in coal, including sulfur. Around the world, coal is the largest source of energy for electricity. The United States is rich in coal. Pennsylvania and the region to the west of the Appalachian Mountains are some of the most coal-rich areas of the United States. Coal has to be mined to get it out of the ground. Coal mining affects the environment and human health. Coal mining can take place underground or at the surface. Each method has some advantages and disadvantages. Surface mining exposes minerals that were underground to air and water at the surface. These minerals contain the chemical element sulfur. Sulfur mixes with air and water to make sulfuric acid. This acid is a highly corrosive chemical. Sulfuric acid gets into nearby streams and can kill fish, plants, and animals. Surface mining is safer for the miners. Coal mining underground is dangerous for the coal miners. Miners are sometimes killed if there is an explosion or a mine collapse. Miners breathe in coal dust and can get terrible lung diseases after a number of years in the mines. To prepare coal for use, the coal is first crushed into powder and burned in a furnace. Like other fuels, coal releases most of its energy as heat when it burns. The heat from the burning coal is used to boil water. This makes steam. The steam spins turbines, which creates electricity. Oil is a thick, dark brown or black liquid. It is found in rock layers of the Earths crust. Oil is currently the most commonly used source of energy in the world. The way oil forms is similar in many ways to coal. Tiny organisms like plankton and algae die and settle to the bottom of the sea. Sediments settle over the organic material. Oxygen is kept away by the sediments. When the material is buried deep enough, it is exposed to high heat and pressure. Over millions of years, the organic material transforms into liquid oil. The United States produces only about one-quarter as much oil as it uses. The main oil producing regions in the U.S. are the Gulf of Mexico, Texas, Alaska, and California. Geologists look for oil in folded layers of rock called anticlines. Oil moves through permeable rock and is trapped by the impermeable cap rock. Oil comes out of the ground as crude oil. Crude oil is a mixture of many different hydrocarbons. Oil is separated into different compounds at an oil refinery (Figure 5.4). This is done by heating the oil. Each hydrocarbon compound in crude oil boils at a different temperature. We get gasoline, diesel, and heating oil, plus waxes, plastics, and fertilizers from crude oil. These fuels are

SOLUTION:
The fossil fuel that is the biggest contributor to global warming is