Which of the following is an example of unauthorized practice of law?

The act of representing a corporation without a license is indeed an example of unauthorized practice of law. In California, as well as in many other jurisdictions, only licensed attorneys are permitted to represent parties, including corporations, in legal matters. This requirement exists to ensure that the individuals acting on behalf of a corporation possess the necessary legal knowledge and expertise to navigate complex legal issues effectively. Representation of a corporation involves interpreting laws, making legal arguments, and potentially appearing in court, which requires an understanding of legal principles that unlicensed individuals do not possess.

In contrast, advising a friend on a legal matter does not typically constitute the unauthorized practice of law, especially if the advice is informal and does not involve a professional relationship or compensation. Filing documents without authorization might raise ethical concerns but isn't explicitly categorized as unauthorized practice of law unless performed without any authority whatsoever. Teaching a legal course at a university can be done by individuals who may not be practicing lawyers, as long as they are qualified to teach the subject matter and are not representing themselves as practicing attorneys.

Thus, when examining the nature of legal representation and the qualifications required to act on behalf of another, representing a corporation without a license clearly illustrates a violation of the legal standards governing the practice of law.