On 1/1/19, Casey Co. sold inventory to Lemon, Inc. for $100,000 cash that had a cost of $40,000. Lemon, Inc. subsequently sold half that inventory during the year at a sales price of $300,000 to unrelated third parties. Casey Co. and Lemon, Inc. are related companies subject to consolidation. The portion of the elimination entry at the time of consolidation to account for any required adjustment to the cost of goods sold account would be:

a) Debit to Cost of Goods Sold of $90,000

b) Credit to Cost of Goods Sold of $70,000

c) Credit to Cost of Goods Sold of $200,000

d) Credit to Cost of Goods Sold of $40,000

Please explain step-by-step. Thank you