15. A business warehouse is completely destroyed by fire on October 29, 2021. The taxpayer purchased the warehouse in 2015 for $750,000, and its adjusted basis is $400,000. The taxpayer receives $900,000 from the insurance company on February 25, 2022. What amount must the taxpayer reinvest in qualified replacement property to defer the entire $500,000 realized gain from involuntary conversion? a. $750,000 b. $400,000 c. $900,000 d. $500,000 e. None of these