单项选择题

In every society it is necessary to have a general system of laws to ensure justice. Laws are designed to make certain that people’s rights are protected and that people respect each other’s rights. Sometimes, however, laws are passed which are specific to a time or situation. For example, a town in Indiana once passed a law making it illegal to shoot open a can of food. Apparently, some gun-carrying citizens forgot their can openers and naturally enough, used their guns to do the job. This disturbed other citizens, and endangered their lives, so a law was passed to prevent it.
Specific laws sometimes remain in existence long after the problem has disappeared. The laws then seem strange. For example, the Indiana law was no longer necessary when citizens stopped carrying guns and using them as can-openers. Since the law was no longer needed, what once made sense now seems like nonsense.
Sometimes laws designed to serve a good purpose were passed but somehow these became mixed up in their .wording. As a result, the laws don’t make sense. In one state there is a law which says that it is "illegal to move or to attempt to move a motor vehicle." Obviously, a massive traffic jam would occur if everyone suddenly obeyed that law. But no one does, of course, because the intention of the law was not to prevent owners from moving their own cars. It was to prevent people from moving (stealing) other people’s cars. It is often harder to repeal a law than to pass one, so many of these old laws remain in existence. Because they no longer fit the way people live or because the problem no longer exists, these laws are ignored. Everyone understands that and life goes on. Thus, laws that once made very good sense now seem like nonsense. According to the passage, laws are designed for the purpose of ______.