Given the following Ending Inventory errors for the Portland Company Ending Inventory Error Year Understated $40 2020 Understated $30 2021 Indicate the error in the following items: Select one: a. 2021 Net Income 12/31/21 Retained Earnings Overstated $40 Understated $70 b. 2021 Net Income 12/31/21 Retained Earnings JN 1 2021 Net Income 12/31/21 Retained Earnings Understated $30 Understated $70 d. 2021 Net Income 12/31/21 Retained Earnings Overstated $10 Understated $30 2021 Net Income 12/31/21 Retained Earnings Overstated $30 Overstated $10