Which of the following crimes can involve the unauthorized access of computer systems?

The correct choice is identity theft, as it specifically involves the unauthorized access of computer systems to obtain personal information about an individual. In identity theft, perpetrators often hack into databases, online accounts, or other electronic communication channels to retrieve sensitive data like Social Security numbers, bank details, or credit card information without the victim's consent.

The other options, while they represent serious crimes, do not inherently involve unauthorized access to computer systems. Burglary typically refers to breaking and entering a physical structure with the intent to commit a crime, usually involving a property. Robbery involves taking property from a person through force or threat, which is primarily a physical confrontational crime. Assault likewise pertains to physical harm or the threat of harm to an individual and does not involve or require accessing computer systems. Therefore, identity theft is the only option among the choices that clearly connects with the unauthorized access of digital information.