Which of the following is NOT a problem or criticism with a legal definition of crime? a. Some behaviors are prohibited by the criminal law but the law is not routinely enforced. b. Some behaviors arguably should be prohibited by the criminal law, although they are not. c. Some behaviors are prohibited by the criminal law but, arguably, should not be d. All of the choices are problems or criticisms

In looking at the legal definition of a crime, it can be defined as an action that breaks the law and may be punished. There are criticisms associated with crime and with the definition of a crime. Therefore, I believe the last answer, which is all of the above, are problems or criticisms of the legal definition of a crime.
One criticism of the law is that it is not routinely enforced. An example of this would be speeding. Going one mile per hour over the speed limit is breaking the law, yet that is rarely enforced.
Another issue is that some people feel certain behaviors should be considered crimes, but they aren’t considered crimes. For example, during an election cycle, people constantly get phone calls about candidates that they don’t want to receive. In some cases, that is legal. However, some people believe it should be illegal to call your house about a candidate if you don’t want the call. Some people feel it should be illegal for wealthy people to not pay taxes. However, there are legal ways that wealthy people can avoid paying taxes.
Finally, some actions are viewed as illegal, but shouldn’t be. For example, a minor is not allowed to consume alcohol. However, some religious practices require the consumption of alcohol. Additionally, during Prohibition, it was illegal to make, transport, or sell alcohol, yet this behavior was very common, even among the police. In some countries, alcohol consumption is legal while in others it isn’t legal.
Therefore, I believe that the last answer  “all of the above” is the correct answer to your question.
http://www.psychlotron.org.uk/newResources/criminological/A2_AQB_crim_problemsDefiningCrime.pdf

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