Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

Example Input: The 80-string koto (or hachijugen) was an invention of Japanese composer Michio Miyagi which appeared In 1923.
Example Output: By whom was 80-string koto discovered?

Example Input: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a small vessel disease of the brain caused by mutations in the NOTCH3 gene. CADASIL progresses, in some cases, to subcortical dementia with a particular cognitive impairment. Different diseases in the dementia spectrum share a central cholinergic and sensorimotor plasticity alteration. We aimed to study different intracortical circuits and sensorimotor plasticity in CADASIL patients using transcranial magnetic stimulation protocols, and to determine whether these characteristics correlated with the results of clinical neuropsychological evaluation. Ten CADASIL patients and 10 healthy subjects were included in the study. All subjects underwent a transcranial magnetic stimulation study examining different intracortical circuits. Sensorimotor plasticity was also assessed using a paired associative stimulation and extensive neuropsychological tests. CADASIL patients showed a lack of intracortical facilitation, short latency afferent inhibition and sensorimotor plasticity when compared with control subjects. CADASIL patients also showed an altered neuropsychological profile. Correlation between sensorimotor plasticity and neuropsychological alterations was observed in CADASIL patients. These results suggest that acetylcholine and glutamate could be involved in the dementia process in CADASIL and that abnormal sensorimotor plasticity correlates with the neuropsychological profile in CADASIL patients.
Example Output: Which gene is involved in CADASIL?

Example Input: Weathering changes solid rock into sediments. Sediments are different sizes of rock particles. Boulders are sedi- ments; so is gravel. At the other end, silt and clay are also sediments. Weathering causes rocks at the Earths surface to change form. The new minerals that form are stable at the Earths surface. It takes a long time for a rock or mountain to weather. But a road can do so much more quickly. If you live in a part of the world that has cold winters, you may only have to wait one year to see a new road start to weather (Figure Mechanical weathering breaks rock into smaller pieces. These smaller pieces are just like the bigger rock; they are just smaller! The rock has broken without changing its composition. The smaller pieces have the same minerals in the same proportions. You could use the expression a chip off the old block to describe mechanical weathering! The main agents of mechanical weathering are water, ice, and wind. Rocks can break apart into smaller pieces in many ways. Ice wedging is common where water goes above and below its freezing point (Figure 9.2). This can happen in winter in the mid-latitudes or in colder climates in summer. Ice wedging is common in mountainous regions. This is how ice wedging works. When liquid water changes into solid ice, it increases in volume. You see this when you fill an ice cube tray with water and put it in the freezer. The ice cubes go to a higher level in the tray than the water. You also may have seen this if you put a can of soda into the freezer so that it cools down quickly. If you leave the can in the freezer too long, the liquid expands so much that it bends or pops the can. (For the record, water is very unusual. Most substances get smaller when they change from a liquid to a solid.) Abrasion is another type of mechanical weathering. With abrasion, one rock bumps against another rock. Gravity causes abrasion as a rock tumbles down a slope. Moving water causes abrasion it moves rocks so that they bump against one another (Figure 9.3). Strong winds cause abrasion by blasting sand against rock surfaces. Finally, the ice in glaciers cause abrasion. Pieces of rock embedded in ice at the bottom of a glacier scrape against the rock below. If you have ever collected beach glass or pebbles from a stream, you have witnessed the work of abrasion. Sometimes biological elements cause mechanical weathering. This can happen slowly. A plants roots grow into a crack in rock. As the roots grow larger, they wedge open the crack. Burrowing animals can also cause weathering. By digging for food or creating a hole to live in the animal may break apart rock. Today, human beings do a lot of mechanical weathering whenever we dig or blast into rock. This is common when we build homes, roads, and subways, or quarry stone for construction or other uses. Mechanical weathering increases the rate of chemical weathering. As rock breaks into smaller pieces, the surface area of the pieces increases. With more surfaces exposed, there are more places for chemical weathering to occur. Lets say you wanted to make some hot chocolate on a cold day. It would be hard to get a big chunk of chocolate to dissolve in your milk or hot water. Maybe you could make hot chocolate from some smaller pieces like chocolate chips, but it is much easier to add a powder to your milk. This is because the smaller the pieces are, the more surface area they have. Smaller pieces dissolve more easily. Chemical weathering is different than mechanical weathering. The minerals in the rock change. The rock changes composition and becomes a different type of rock. Most minerals form at high pressure or high temperatures deep within Earth. But at Earths surface, temperatures and pressures are much lower. Minerals that were stable deeper in the crust are not stable at the surface. Thats why chemical weathering happens. Minerals that formed at higher temperature and pressure change into minerals that are stable at the surface. Chemical weathering is important. It
Example Output:
weathering process that occurs when rocks and rock particles scrape other rocks