The taxpayer should receive a full refund of $750 for the excess accumulation penalty they paid. Here's the explanation: Penalty Assessment: The IRS assessed a $750 penalty for not taking out the entire RMD of $8,000 in the previous year. Correction: The taxpayer voluntarily corrected the mistake the following year by withdrawing the remaining $3,000 ($8,000 total RMD - $5,000 initial withdrawal). Refund Eligibility: The Internal Revenue Service (IRS) allows taxpayers to recoup excess accumulation penalties if they correct the shortfall within two years of the missed RMD and pay any taxes due on the additional distribution. Since the taxpayer acted within the two-year window and addressed the shortfall, they are eligible for a full refund of the $750 penalty. Therefore, the answer is: a. $750