The police do many things for us. They help keep our things and us safe. They help keep cars moving safely. They take care of people who are hurt. Then they see these people get to a doctor. The police go around town to see that everything is all right. They get around town in many ways. Some of them walk or go by car. In some big cities,some of the police ride on horses. It is strange to see these animals in the street. As they go around town,the police help people. Sometimes they find lost children. They take the children home. If the police see a fight,they put an end to it right away. Sometimes people will ask the police how to get to a place in town. The police can always tell the people which way to go. They know all the streets and roads well. Some police stand at crossings. They tell the cars when to go and when to stop. They make sure that the cars do not go too fast. They help children cross the street. They also help people who can't walk too well. Without the police,our streets would not be safe. Cars might go too fast and hurt people. Lost people might never be found. The police do a good job. We need them. And we should thank them for a job well done. The police do many things for us. They help keep our things and us   _  .
warm clean quiet safe
Question: The police do many things for us. They help keep our things and us safe. They help keep cars moving safely. They take care of people who are hurt. Then they see these people get to a doctor. The police go around town to see that everything is all right. They get around town in many ways. Some of them walk or go by car. In some big cities,some of the police ride on horses. It is strange to see these animals in the street. As they go around town,the police help people. Sometimes they find lost children. They take the children home. If the police see a fight,they put an end to it right away. Sometimes people will ask the police how to get to a place in town. The police can always tell the people which way to go. They know all the streets and roads well. Some police stand at crossings. They tell the cars when to go and when to stop. They make sure that the cars do not go too fast. They help children cross the street. They also help people who can't walk too well. Without the police,our streets would not be safe. Cars might go too fast and hurt people. Lost people might never be found. The police do a good job. We need them. And we should thank them for a job well done. The police do many things for us. They help keep our things and us   _  .
A. warm
B. clean
C. quiet
D. safe
Answer: