For this research，the satellite Worldview 3 used high-quality pictures to monitor African elephants moving through forests and grasslands. The automated（自动化）system detected animals with the same accuracy as humans are able to achieve. The new surveying technique，created by Dr. Olga Isupova at the University of Bath in the UK with some other scientists，allows vast areas of land to be scanned in a matter of minutes，offering a much-needed alternative to human observers counting individual animals from low-flying airplanes. As it sweeps across the land，a satellite can collect over 5，000 km2 of pictures every few minutes，avoiding double counting. Where necessary， the process can be repeated the next day. The population of African elephants has nose-dived over the past century，mainly due to hunting illegally and habitat（栖息地） ruin. With only 40，000-50，000 elephants left in the wild，the species is classified as endangered. "Accurate monitoring is essential if we're to save the species，" said Dr. Isupove. "We need to know where the animals are and how many there are." Satellite monitoring avoids disturbing animals during date collection and ensures humans are not hurt in the counting process. It also makes it simpler to count animals moving from country to country， as satellites can orbit the planet without regard for border controls or conflict. This study was not the first to use satellite pictures and algorithms（计数法）to monitor species，but it was the first to reliably monitor animals moving through a complex environment ---that is，an environment that includes areas of open grassland， woodland and partial coverage. "This type of work has been done before with whales， but of course the ocean is all blue， so counting is a lot less challenging，" said Dr. Isupova. "As you can imagine， a complex environment makes it much harder to identify animals." The researchers believe their work shows the potential of technology to support environmentalists to protect biodiversity and to slow the progress of the sixth mass extinction（灭绝）---the ongoing extinction event caused by human activity.（1）Why did the scientists create the satellite cameras？ ____

Scientists have successfully used satellite cameras to count animals in complex geographical environments，taking environmentalists an important step forward in monitoring populations of endangered species.
    For this research，the satellite Worldview 3 used high-quality pictures to monitor African elephants moving through forests and grasslands. The automated（自动化）system detected animals with the same accuracy as humans are able to achieve. The new surveying technique，created by Dr. Olga Isupova at the University of Bath in the UK with some other scientists，allows vast areas of land to be scanned in a matter of minutes，offering a much-needed alternative to human observers counting individual animals from low-flying airplanes. As it sweeps across the land，a satellite can collect over 5，000 km² of pictures every few minutes，avoiding double counting. Where necessary， the process can be repeated the next day.
    The population of African elephants has nose-dived over the past century，mainly due to hunting illegally and habitat（栖息地） ruin. With only 40，000-50，000 elephants left in the wild，the species is classified as endangered.
    "Accurate monitoring is essential if we're to save the species，" said Dr. Isupove. "We need to know where the animals are and how many there are." Satellite monitoring avoids disturbing animals during date collection and ensures humans are not hurt in the counting process. It also makes it simpler to count animals moving from country to country， as satellites can orbit the planet without regard for border controls or conflict.
     This study was not the first to use satellite pictures and algorithms（计数法）to monitor species，but it was the first to reliably monitor animals moving through a complex environment ---that is，an environment that includes areas of open grassland， woodland and partial coverage. "This type of work has been done before with whales， but of course the ocean is all blue， so counting is a lot less challenging，" said Dr. Isupova. "As you can imagine， a complex environment makes it much harder to identify animals."
    The researchers believe their work shows the potential of technology to support environmentalists to protect biodiversity and to slow the progress of the sixth mass extinction（灭绝）---the ongoing extinction event caused by human activity.
（1）Why did the scientists create the satellite cameras？ ____
A. To count animals in complex environment.
B. To increase the number of wild animals.
C. To train the skills of observing animals.
D. To drive the elephants out of forests in Africa.
（2）What can we learn about the new surveying technique？ ____
A. It's individual.
B. It's complex.
C. It's dangerous.
D. It's accurate.
（3）What is the condition of African elephants？ ____
A. They are rapidly increasing.
B. They are in diversity.
C. They are rapidly reducing.
D. They are in balance.
（4）What would be the best title for this passage？ ____
A. Making the Satellite Worldview 3 for Biodiversity.
B. Using Satellite to Monitor Endangered Species.
C. Supporting Hunting with new Technology.
D. Introducing Dr. Olga Isupova at the University of Bath.