单项选择题

PassageTwo Questions26to30arebasedonthefollowingpassage. FalseteethhavebeenfoundinItalyinhumanheadsthatareover2，500yearsold.Theyweremadeofboneandsetingold.However，forhundredsofyearsafterwards，theapparentdentalskillofthoseearlypeoplewaslost.Withoutfalseteethpeoplelookedoldbeforetheirtime，sincesomanylosttheirteethatanearlyage. Towardtheendofthe17thcentury，richpeoplecouldbuyfalseteethmadefromivory.Theteethweretiedtogetherwithsilkthread，butitwasdifficulttokeeptheminthemouth.Thatwaswhyrichpeoplewouldratherbuyteethfromthepoorwhowouldoftenselltheirteethtobuyfoodandclothing. Earlyinthe18thcenturyaFrenchdoctorusedsteelspringstoholdteethinplace.However，itwasdifficulttocloseone‘smouth！Lateinthesamecenturyporcelain（瓷）teethsetingoldwereoftenusedtomakefalseteeth. Althoughtheuseofartificialteethincreased，humanteethcontinuedtobeusedalso.Inthe19thcentury，teethfromsoldierskilledinbattleweremadeintoartificialteeth.Forexample，teethfromthedeadintheAmericanCivilWarweresenttoEngland. Bythemiddleofthe19thcentury，anAmericandoctor，ClaudiusAsh，inventedabetterkindofporcelaintoothmadeofaspecialkindofhardrubber. Thepassageismainlyabout___________.

A．the discovery of false teeth
B．the material of false teeth
C．the use of false teeth
D．the history of false teeth
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单项选择题
Whichofthefollowingstatementsistrueaccordingtothepassage？
A．Trademarks must be attached to all products.
B．Service marks not only identify products but also help to advertise services.
C．Laws to protect trademark owners were probably developed between 1801-1810.
D．Local registration is the only protection for trademark rights.
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WhatisbeingdonetomakeT-shirtsmoreattractive？
A．A variety of new styles are being designed.
B．The price is being lowered again and again.
C．Advertisements are being widely used.
D．The traditionally used material is being replaced.
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