ReadthefollowingpassageandmarktheletterA,B, C,orD onyouranswersheettoindicatethecorrectanswertoeachofthe questions.

ThecountrysideofBritainiswellknownforitsbeautyandmanycontrasts: itsbaremountainsandmoorland,itslakes,riversandwoods,anditslong,often wildcoastline.Manyofthemostbeautifulareasarenationalparksandareprotectedfromdevelopment.WhenBritishpeoplethinkofthecountrysidethey thinkoffarmland,aswellasopenspaces.Theyimaginecowsorsheepingreen fieldsenclosedbyhedgesorstonewalls,andfieldsofwheatandbarley.Most farmland is privately owned but is crossed by a network of public footpaths.

Manypeopleassociatethecountrysidewithpeaceandrelaxation.Theyspend theirfreetimewalkingorcyclingthere,orgotothecountryforapicnicora publunch. Insummerpeoplegotofruitfarmsandpickstrawberriesandother fruit.Onlyafewpeoplewholiveinthecountryworkonfarms.Manycommute toworkintowns.Manyothersdreamoflivinginthecountry,wherethey believe they would have a better and healthier lifestyle.

Thecountrysidefacesmanythreats.Someareassociatedwithmodern farmingpractices,andtheuseofchemicalsharmfultoplantsandwildlife.Land isalsoneededfornewhouses.Thegreenbelt,anareaoflandaroundmany cities,isunderincreasingpressure.Planstobuildnewroadsarestrongly opposedbyorganizationstryingtoprotectthecountryside.Protesterssetup camps to prevent, or at least delay, the building work.

Americahasmanyareasofwildandbeautifulscenery,andtherearemany areas,especiallyintheWestinstateslikeMontanaandWyoming,wherefew people live. In the New Englandstates, suchas Vermont andNewHampshire, itiscommontoseesmallfarmssurroundedbyhillsandgreenareas.InOhio, Indiana,IllinoisandotherMidwesternstates,fieldsofcornorwheatreachto the horizon and there are manymiles between towns.

Onlyabout20%ofAmericansliveoutsidecitiesandtowns.Lifemaybe difficultforpeoplewholiveinthecountry.Services likehospitals and schools maybefurtherawayandgoingshoppingcanmeandrivinglongdistances. Somepeopleevenhavetodrivefromtheirhomestothemainroadwheretheir mailis left inabox.Inspiteofthedisadvantages, manypeoplewholive inthe countrysaythattheylikethesafe,clean,attractiveenvironment.Buttheir children often move to a town or city as soon as they can.

AsinBritain,Americansliketogoouttothecountryatweekends.Some people go on camping or fishing trips, othersgo hiking in national parks.

According to the passage, what makes mobile phones potentially harmful is ______.