What will be the benefit if the research on smart windows turns out to be successful, according to the last paragraph?A．The buildings will look different.B．Windows can be as large as you want.C．We may not need air conditioners any more.D．They are less exp

What will be the benefit if the research on smart windows turns out to be successful, according to the last paragraph?

A．The buildings will look different.

B．Windows can be as large as you want.

C．We may not need air conditioners any more.

D．They are less expensive than traditional windows.