The reflective towers of NewYork City,which is on the Atlantic migrating（迁徙的）route ,can bedeadly for birds.“We live in an age of glass,” said Ms.Laurel,an architect.“It can be a perfect mirror in certain lights,and the larger the glas

The reflective towers of NewYork City,which is on the Atlantic migrating（迁徙的）route ,can bedeadly for birds.“We live in an age of glass,” said Ms.Laurel,an architect.“It can be a perfect mirror in certain lights,and the larger the glas
The reflective towers of New
York City,which is on the Atlantic migrating（迁徙的）route ,can be
deadly for birds.“We live in an age of glass,” said Ms.Laurel,an architect.
“It can be a perfect mirror in certain lights,and the larger the glass,the
more dangerous it is.” About 90,000 birds are killed by flying into building in
the city each year.Often,they strike the lower levels of glass towers after
searching for food in nearby parks.Such crashes are the second-leading cause
of death for migrating birds,after habitat（栖息地）loss,with an
estimated number of death ranging up to a billion a year.
　　As glass office
and apartment towers have increased in the last decade,so,too,have calls to
make them less deadly to birds.San
Francisco adopted bird-safety standard for new
building in July.The United States Green Building Council,a nonprofit
industry group that encourages the creation of environmentally conscious
buildings,will introduce a bird-safety credit this as part of its
environmental certification process.
　　There are no easy
fixes,however.A few researchers are exploring glass designs that use
ultraviolet（紫外线的）signals,but they are still
in their infancy.Covers,dot patterns,shades and net are the main options
available.
　　Often,only one
section of a building needs to be changed.“You don't necessarily have to treat
every window,” Ms.Laurel said.“It would be too expensive to do the whole
building.” The Jacob
Convention Center,which
has been undergoing alterations,is the most recent building to voluntarily
correct the problem of bird crashes.The architects used less reflective glass
and dot patterns.
What is the main idea ofthe passage?
　　A.New York is a city ofglass towers.
　　B.Glass towerare dangerous for migrating birds.
　　C.New York adopted newsafety standards for buildings.
　　D.Glass towers are a new trend in the United States.

The reflective towers of NewYork City,which is on the Atlantic migrating（迁徙的）route ,can bedeadly for birds.“We live in an age of glass,” said Ms.Laurel,an architect.“It can be a perfect mirror in certain lights,and the larger the glas
B

C

选C