In the last line of the passage, the word "excused" probably means ______.

A．front seat passenger should be over 14 years old
B．drivers must make sure that front seat passengers wear their belts
C．both the driver and the front seat passenger must wear a seat belt
D．a driver needn't know whether the front seat passenger is over 14 or not

A．you will not be fined if you drive a vehicle to deliver milk
B．a child under 14 can sit in the front seat
C．front seat passenger must be fined in any case
D．a doctor can drive a car and not be fined