Under treasury circular 230, which of the following actions of a cpa tax advisor is characteristic of a best practice in rendering tax advice? a. requesting written evidence from a client that the fee proposal for tax advice has been approved by the board of directors. b. establishing relevant facts, evaluating the reasonableness of assumptions and representations, and arriving at a conclusion supported by the law and facts in a tax memorandum. c. recommending to the client that the advisor's tax advice be made orally instead of in a written memorandum. d. requiring the client to supply a written representation, signed under penalties of perjury, concerning the facts and statements provided to the cpa for preparing a tax memorandum. e. all of the above