This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: The first real progress toward a modern understanding of nervous function, though, came from the investigations of Luigi Galvani, who discovered that a shock of static electricity applied to an exposed nerve of a dead frog could cause its leg to contract. Since that time, each major advance in understanding has followed more or less directly from the development of a new technique of investigation. Until the early years of the 20th century, the most important advances were derived from new methods for staining cells. Particularly critical was the invention of the Golgi stain, which (when correctly used) stains only a small fraction of neurons, but stains them in their entirety, including cell body, dendrites, and axon. Without such a stain, brain tissue under a microscope appears as an impenetrable tangle of protoplasmic fibers, in which it is impossible to determine any structure. In the hands of Camillo Golgi, and especially of the Spanish neuroanatomist Santiago Ramón y Cajal, the new stain revealed hundreds of distinct types of neurons, each with its own unique dendritic structure and pattern of connectivity.

Answer: Who found out that a shock of electricity to an exposed nerve of a dead frog caused contractions?


Question: After World War II, two new competing formats came onto the market and gradually replaced the standard "78": the 33 1⁄3 rpm (often just referred to as the 33 rpm), and the 45 rpm (see above). The 33 1⁄3 rpm LP (for "long-play") format was developed by Columbia Records and marketed in June 1948. RCA Victor developed the 45 rpm format and marketed it in March 1949, each pursuing their own r&d in secret. Both types of new disc used narrower grooves, intended to be played with smaller stylus—typically 0.001 inches (25 µm) wide, compared to 0.003 inches (76 µm) for a 78—so the new records were sometimes called Microgroove. In the mid-1950s all record companies agreed to a common recording standard called RIAA equalization. Prior to the establishment of the standard each company used its own preferred standard, requiring discriminating listeners to use pre-amplifiers with multiple selectable equalization curves.

Answer: What two formats replaced the 78?


Question: Controversy persists over whether the Rus’ were Varangians (Vikings) or Slavs. This uncertainty is due largely to a paucity of contemporary sources. Attempts to address this question instead rely on archaeological evidence, the accounts of foreign observers, legends and literature from centuries later. To some extent the controversy is related to the foundation myths of modern states in the region. According to the "Normanist" view, the Rus' were Scandinavians, while Russian and Ukrainian nationalist historians generally argue that the Rus' were themselves Slavs. Normanist theories focus on the earliest written source for the East Slavs, the Russian Primary Chronicle, although even this account was not produced until the 12th century. Nationalist accounts have suggested that the Rus' were present before the arrival of the Varangians, noting that only a handful of Scandinavian words can be found in modern Russian and that Scandinavian names in the early chronicles were soon replaced by Slavic names. Nevertheless, archaeological evidence from the area suggests that a Scandinavian population was present during the 10th century at the latest. On balance, it seems likely that the Rus' proper were a small minority of Scandinavians who formed an elite ruling class, while the great majority of their subjects were Slavs. Considering the linguistic arguments mounted by nationalist scholars, if the proto-Rus' were Scandinavians, they must have quickly become nativized, adopting Slavic languages and other cultural practices.

Answer:
What controversy currently surrounds the Rus?