According to the AICPA Statement on Standards for Tax Services, which of the following statements is correct regarding the standards a CPA should follow when recommending tax return positions and preparing tax returns?

a. A CPA may recommend a position that the CPA concludes is frivolous as long as the position is adequately disclosed on the return.

b. A CPA may recommend a position in which the CPA has a good faith belief that the position has a realistic possibility of being sustained if challenged.

c. A CPA will usually not advise the client of the potential penalty consequences of the recommended tax return position.

d. A CPA may sign a tax return as preparer knowing that the return takes a position that will not be sustained if challenged.