On January 1, 2020, Miner Corp. changed its inventory costing from FIFO to average cost for financial statement and income tax purposes, to make their reporting as reliable and more relevant. The change resulted in a $ 600,000 increase in the beginning inventory at January 1, 2020. Assume a 30% income tax rate. The cumulative effect of this accounting change should be reported by Chickadee in its 2020

a. Income statement as $ 420,000 other comprehensive income.

b. Income statement as a $ 600,000 cumulative effect of accounting change.

c. Retained earnings statement as a $ 600,000 addition to the beginning balance.

d. Retained earnings statement as a $ 420,000 addition to the beginning balance.