What would be the best title for the passage ______.

A．It has reduced the costs of medical treatment.
B．It has helped save the lives of most patients.
C．It has encouraged doctors to do more heart surgeries.
D．It have helped educate people about the prevention of heart disease.

A．lengthening the existing 53-kilometer subway is among the 50 large projects
B．the length of the subway will be up to 135.25 kilometers in 2005
C．a 40.5-meter-long line will be added to Beijing's first light railway
D．a 70-meter-wide green belt will supply us with enough water