An attorney shall not make a false or misleading communication about the attorney or the attorney's services. A communication is false or misleading if it:

(a) contains a material misrepresentation of fact or law, or omits a fact necessary to make the statement considered as a whole not materially misleading;

(b) is likely to create an unjustified expectation about results the attorney can achieve, or states or implies that the attorney can achieve results by means that violate the Maryland Attorneys' Rules of Professional Conduct or other law; or

(c) compares the attorney's services with other attorneys' services, unless the comparison can be factually substantiated.