CPA Rick has for many years prepared the individual income tax returns for his client, Luka. In preparing this year’s return, Rick discovered a material error in last year’s return that caused Luka to substantially underpay her taxes. Which of the following is the best answer?

a. Rick must promptly tell Luka of the error.

b. Rick must promptly tell the IRS of the error.

c. Rick should consider not preparing Luka’s tax returns in the future if Luka refuses to bring the error to the IRS’s attention.

d. Rick must promptly tell Luka of the error and Rick should consider not preparing Luka’s tax returns in the future if Luka refuses to bring the error to the IRS’s attention.