题目内容
（请给出正确答案）
[单选题]
Passage Two, 问题1
A.2-1A
B.2-1B
C.2-1C
D.2-1D
提问人：网友tianfeng722
发布时间：2022-01-07
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PassageTwo
Questions26to30arebasedonthefollowingpassage.
Doctorshavelongknownthateatingfishhelpsprotectagainstheartdisease.
Whattheydon’tknowiswhyfisharebeneficial.Foryearstheyfigureditwasasimplequestionofsubstitution:
folkswhoreplaceredmeatwithfisharenaturallycuttingdowntheirintakeofsaturated(饱和的)fat.Butagrowingbodyofevidencecollectedoverthepast30yearssuggestsfishcontainhealthfulelementscalledomega-3fattyacids.
Omega-3fattyacidsbelongtoagroupofcompoundsknownaspolyunsaturatedfats.
Thesefatsserveastherawmaterialforawholehostofessentialstructuresinthebody,
frombraincellstomolecules(分子)thatregulatebloodpressure.
Sinceourbodiescannotmanufacturetheirownsupplyofomega-3s,wehavetogetthemfromthefoodweeat,mostlyfromfishbutalsofromplantsourceslikesoybeans(大豆).
TheAmericanHeartAssociationhasrecommendedthateveryoneeattwo85-gservingsoffattyfishaweek.ButtheA.H.A’sexpertpanelwasn’treadytodeclarethattakingomega-3pillswillprotectyourheart.It’sjusttooeasytogetmoreomega-3thanyouneedfrompills,andthepanelwasworriedthatanexcesscouldcauseserioussideeffects,suchasinternalbleeding.
TheU.S.FoodandDrugAdministration,however,allowedmanufacturesofomega-3pillsandfishoilstoadvertisethefat’sbenefits—aslongasthelabeldoesnotsuggesttakingmorethantwogramsperday.
Onethingisclearwhetheryougetyouromega-3sfrompills,oilsorfish:theyarenotcure-alls.Youstillhavetoeatawell-balanceddietthat’slowerintotalfatthanmostAmericanscurrentlyconsume.Otherwise,you’refishingfortrouble.
26.Doctorshavelongbeenpuzzledby.
A.whyredmeatisharmful
B.howbeneficialfishare
C.whatmakesfishhealthful
D.howredmeatisreplaced
