A．provide more healthy food
B．ban food advertisements at schools
C．arrange more physical education classes
D．teach students to keep fit

A． The number of school injuries has doubled in ten year
B． About 20% of American children and teenagers are overweigh
C． Only 2% of the injuries treated in hospitals are seriou
D． Injuries increased 1．5 times as many as that during the past decad

A． are more competitive
B． are less risky
C． involve more activities
D． provide less choices