In $2022,$ Alpha Dog Inc. changed its method of valuing inventory from the average cost method to the FIFO method. At December $31,2021,$ Alpha's inventories were $$47\mathrm{.}6$ million $($average cost$).$ Alpha's records indicated that the inventories would have totaled $$64$ million at December $31,2021,$ if determined on a FIFO basis. Ignoring income taxes, the journal entry to record the adjustment in $2022$ would include:

A$.$ A credit to Inventory for $$64$ million

B$.$ A credit to Retained Earnings for $$16\mathrm{.}4$ million

C$.$ A debit to Retained Earnings for $$16\mathrm{.}4$ million

D$.$ A debit to Inventory for $$64$ million