a. The statement is correct. One reason for the difficulty faced by the police in preventing computer-related crimes is that many such crimes are not reported to the authorities, and it is also challenging for them to keep up with the necessary technological skills.

b. While this statement is not entirely wrong, it is not directly related to the main argument presented in the paragraph. The paragraph discusses the challenges faced by the police in preventing computer-related crimes and why many such crimes go unreported. It does not focus on how computers can help the police solve other types of crimes.