问题：

[单选] 根据以下材料，回答题
[A] Some archaeological sites have alwaysbeen easily observable—for example, the Parthenon in Athens, Greece, the pyramids of Gizain Egypt; and the megaliths of Stonehenge in southern England. But these sitesare exceptions to the norm. Most archaeological sites have been located bymeans of careful searching, while many others have been discovered by accident.Olduvai Gorge, an early hominid site in Tanzania, was found by a butterflyhunter who literally fell into its deep valley in 1911. Thousands of Aztecartifacts came to light during the digging of the Mexico City subway in the1970s.

[B]In another case, American archaeologistsRene Million and George Cowgill spent years systematically mapping the entirecity of Teotihuacan in the Valley of Mexico near what is now Mexico City. Atits peak around AD 600, this city was one of the largest human settlements inthe world. The researchers mapped not only the city’s vast and ornateceremonial areas, but also hundreds of simpler apartment complexes where commonpeople lived.

[C] How do archaeologists know where tofind what they are looking for when there is nothing visible on the surface ofthe ground? Typically, they survey and sample (make test excavations on) largeareas of terrain to determine where excavation will yield useful information.Surveys and test samples have also become important for understanding thelarger landscapes that contain archaeological sites.

[D] Surveys can cover a single largesettlement or entire landscapes. In one case, many researchers working aroundthe ancient Maya city of Copan, Honduras, have located hundreds of small ruralvillages and individual dwellings by using aerial photographs and by makingsurveys on foot. The resulting settlement maps show how the distribution anddensity of the rural population around the city changed dramatically between AD500 and 850, when Copan collapsed.

[E] To find their sites, archaeologiststoday rely heavily on systematic survey methods and a variety ofhigh-technology tools and techniques. Airborne technologies, such as differenttypes of radar and photographic equipment carried by airplanes or spacecraft, allowarchaeologists to learn about what lies beneath the ground without digging. Aerialsurveys locate general areas of interest or larger buried features, such asancient buildings or fields.

[F] Most archaeological sites, however, arediscovered by archaeologists who have set out to look for them. Such searchescan take years. British archaeologist Howard Carter knew that the tomb of theEgyptian pharaoh Tutankhamun existed from information found in other sites.Carter sifted through rubble in the Valley of the Kings for seven years before helocated the tomb in 1922. In the late 1800s British archaeologist Sir ArthurEvan