Final answer:
It is indeed professional misconduct for an attorney to abandon a client without following proper withdrawal procedures and ensuring the client is not disadvantaged, as this violates ethical rules in the legal profession.
Step-by-step explanation:
The question asks whether it is professional misconduct to abandon a client. The answer to this question is A. True. In the legal profession, attorneys have a responsibility to provide diligent representation to their clients. Abandoning a client without proper withdrawal procedures, reasonable notice, or ensuring that the client is not prejudiced due to the attorney's departure is considered professional misconduct. Ethical rules, like the American Bar Association's Model Rules of Professional Conduct, often specify the obligations an attorney has to their client, including the requirement to communicate and the prohibition against abandoning a client without cause.