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【分析解答题】Questions 1-9Color in textiles is produced by dyeing, by printing, or by painting. Until thenineteenth century, all dyes were derived from vegetable or, more rarely, animalor mineral sources,Since madder plants could be grown practically everywhere, the roots of somespecies of the madder plant family were used from the earliest period to produce a wholerange of reds. Red animal dyes, derived! from certain species of scale insects, were alsohighly valued from ancient times through the MiddleAges.Blues were obtained fromindigo, which was widely .cultivated in India and exported from there, and from woad,a plant common inEurope and also used in the NearEast from the beginning of theChristian er
A、Before the first, nonfading "solid" green was invented in the earlynineteenth century, greens were achieved by the overdyeing or overprinting of yellowand blue. However, yellow dyes± whether from weld or some other plant source suchas saffron or turmeric, invariably fade or disappear. This accounts for the bluish tingeof what were once bright greens in, for example, woven tapestry.The range of natural colors was hugely expanded and, indeed, superseded by thechemical dyes developed during the eighteen hundreds.By 1900 a complete rangeof synthetic colors had been evolved, many of them reaching a standard of resistanceto fading from exposure to light and to washing that greatly exceeded that of naturaldyestuffs. Since then, [he petroleum industry has added many new chemicals, and fromhese other types of dyestuffs have been developeD、Much of the research in dyes wasstimulated by the peculiarities of some of the new synthetic fibers-Acetate rayon, forexample, seemed at first to have no affinity for dyes and a new range of dyes had to bedeveloped; nylon and Terylene presented similar problems.The printing of textiles has involved a number of distinct methods. With the exceptionof printing patterns directly onto the cloth, whether by block, roller, or screen, all of thesearc based on dyeing; that is, the immersion of the fabric in a dye bath What was the advantage of using madder plants for different shades of red
A、It was possible to cultivate madder plants in almost every location,

B、Madder plants produced brighter colors than other plant sources.
C．Plant sources produced more lasting colors than animal sources.
Dyes derived from the madder plants were easier to work with than other dyes

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