The 2021 Form 10-K of Oracle Corporation, for the May 31, 2021 year-end, included the following information relating to their allowance for doubtful accounts: Balance in allowance at the beginning of the year $305 million, accounts written off during the year of $137 million, balance in allowance at the end of the year $319 million. What did Oracle Corporation report as bad debt expense for the year? Select one: a $27 million O b.5118 million Oc5151 million O d. 5129 million