The local health organization is reported ______ (三十年前成立的) when Mr. Smith became its first mayor.

A．rates
B．ratios
C．proportions
D．percentages

A．their parents drive them to more places
B．they can get more freedom to explore some close places without adult supervision
C．the cars in the city they live must give way to them
D．their parents keep them off the streets for safety