题目内容：
Questions are based on the following passage．Amazon is looking at drastically reducing its delivery times--to 30 minutes orless--as it plans a new service called Prime Air that it says could debut (初次登台 )in a few years. The giant online retailer plans to use semi-autonomous drones ( 无人驾驶飞机 ) to carry purchases to customers. CEO Jeff Bezos announced the plan Sunday onCBS' 60 Minutes.
Bezos tells Charlie Rose, the host that Amazon's "octocopters" could be airbornewithin four to five years, using GPS coordinates to find customers.
"These are effectively drones," Bezos says, "but there's no reason that they can't beused as delivery vehicles."
The drones would depart from the retailer's "fulfillment centers", the hugewarehouses it has built near many large population centers in the U.S. and elsewhere.
They can carry about five pounds, Bezos says, a figure that covers around 85 percent ofAmazon's products.
"I know this looks like science fiction," Bezos tells Rose. "It's not."
The delivery drones would be particularly useful in densely populated urban areas,Bezos says. Powered by electricity, their current range of operation is around 10 milesfrom the point of origin.
Writing that "drones can explode, or run into things," the Quartz technology blog'sHeather Timmons notes that safety concerns may limit where the new delivery devicescould be used.
In addition to safety concerns, drones could face another challenge before they'rewidely used for delivery: overcoming the possible suspicions of citizens whohave mostly seen the unmanned aircraft mentioned in conjunction with military andsurveillance ( 监控 ) uses.
Rose's interview with Bezos also touched on the retailer's 10-year, $600 millioncontract with the CIA through its Amazon Web Services unit. The company is using itstechnological expertise to build a computing cloud for the agency, Bezos said.
When asked by Rose if that presented a conflict, Bezos answered, "We're building
what's called a private cloud for them, Charlie, because they don't want to be on thepublic cloud."
Amazon isn't alone in pursuing drone delivery. Earlier this year, a pilot project byDomino's Pizza looked at flying hot pizzas to customers in Britain, posting a video of asuccessful test run.
That led the site Singularity Hub to observe: "So why are drones such a big deal? Inour robotic future, anything that can reduce urban congestion, minimize carbon emissions,save money and save trips to the emergency room (car accidents kill, you know) willdrive huge value in the economy and make our lives better, to boot."
In order to reduce the delivery times, what does Amazon plan to do? A．Enhance the current air express services.
B．Use the semi-automatic aircrafts to deliver goods.
C．Equip its deliverymen with more advanced vehicles.
D．Use GPS coordinators to deliver goods.
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