Researchers have developed new software using smart phones’GPS and imaging abilities that determine the exact location of distant objects as well as monitor the speed and direction of moving objects．The software could eventually allow smart phone-armed soldiers to target the location of their enemies．On the home front，the software could be used by everyone，including golfers judging distance to the green and biologists documenting the location of a rare animal without disturbing it．
“The great advantage of a Smartphone is that it provides so many tools in a single，readily available，relatively inexpensive package，”said Qia Wang，a doctoral student who led the development of the software．“For example，on the battlefield，a soldier needs a rangefinder，compass，GPS and other tools to get information before calling in an air strike．With our software，the soldier can have all those instruments in one device that can be purchased off the shelf．When that soldier returns from War，she can use the same Software to protect her family by clocking a speeder near her children’s school and catching the criminal on video．”
Wang and his colleagues developed their software to locate and track：
Targets of known size—when the size of the target is known．a single image is enough to pinpoint the target’s location．
Targets of unknown size—If the exact size of a target is unknown，the software uses two images to triangulate the location of the target·
Moving targets—By taking a short video of a moving target，the smartphone software can calculate how fast the target is moving and in what direction it is going.
“Currently，our software is limited by the physical abilities of smartphone hardware，but the devices are improving rapidly，”Wang said．“We expect that improvements in GPS accuracy，battery  life  and  camera  resolution  will  allow  our  software to  make  even  more  accurate observations．”
From Paragraph 1 we can know that the new software can.

A．determine the speed of moving objects

B．1ocate objects in the distance exactly

C．defend soldiers against their enemies

D．help biologists protect rare animal

The example given by Qia Wang is meant to .

A．make an advertisement

B．describe the software briefly

C．show the benefits of the software

D．present the functions of smartphones

How does the software calculate the speed of a moving object?

A．By taking a short video．

B．By locating its position.

C．By taking a single image．

D．By measuring real-life size.

What’s Qia Wang’s attitude towards the future of the software?

A．Casual．

B．Optimistic．

C．Cautious．

D．Flexible

What is the best title of the text?

A．Qia Wang，a Talented Doctoral Student

B．Use Smartphones to Their Full Potential

C．Targeting and Tracking With Smartphones

D．Smartphone-armed Soldiers on the Battlefield