This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[EX Q]: Passage: When World War II started, tonnage levels at the port decreased and shipping activities were suspended; however, the war did provide economic benefits for the city. Petrochemical refineries and manufacturing plants were constructed along the ship channel because of the demand for petroleum and synthetic rubber products by the defense industry during the war. Ellington Field, initially built during World War I, was revitalized as an advanced training center for bombardiers and navigators. The Brown Shipbuilding Company was founded in 1942 to build ships for the U.S. Navy during World War II. Due to the boom in defense jobs, thousands of new workers migrated to the city, both blacks and whites competing for the higher-paying jobs. President Roosevelt had established a policy of non-discrimination for defense contractors, and blacks gained some opportunities, especially in shipbuilding, although not without resistance from whites and increasing social tensions that erupted into occasional violence. Economic gains of blacks who entered defense industries continued in the postwar years. Question: Why did thousands of new workers flock to Houston?
[EX A]: defense jobs

[EX Q]: Passage: The term "Enlightenment" emerged in English in the later part of the 19th century, with particular reference to French philosophy, as the equivalent of the French term 'Lumieres' (used first by Dubos in 1733 and already well established by 1751). From Immanuel Kant's 1784 essay "Beantwortung der Frage: Was ist Aufklarung?" ("Answering the Question: What is Enlightenment?") the German term became 'Aufklarung' (aufklaren = to illuminate; sich aufklaren = to clear up). However, scholars have never agreed on a definition of the Enlightenment, or on its chronological or geographical extent. Terms like "les Lumieres" (French), "illuminismo" (Italian), "ilustracion" (Spanish) and "Aufklarung" (German) referred to partly overlapping movements. Not until the late nineteenth century did English scholars agree they were talking about "the Enlightenment." Question: In what century did the term Enlightenment emerge in English?
[EX A]: 19th

[EX Q]: Passage: Replacing the classical physics in use since the end of the scientific revolution, modern physics arose in the early 20th century with the advent of quantum physics, substituting mathematical studies for experimental studies and examining equations to build a theoretical structure.[citation needed] The old quantum theory was a collection of results which predate modern quantum mechanics, but were never complete or self-consistent. The collection of heuristic prescriptions for quantum mechanics were the first corrections to classical mechanics. Outside the realm of quantum physics, the various aether theories in classical physics, which supposed a "fifth element" such as the Luminiferous aether, were nullified by the Michelson-Morley experimentan attempt to detect the motion of earth through the aether. In biology, Darwinism gained acceptance, promoting the concept of adaptation in the theory of natural selection. The fields of geology, astronomy and psychology also made strides and gained new insights. In medicine, there were advances in medical theory and treatments. Question: The "fifth element" was disproved by what?
[EX A]:
Michelson-Morley experiment