Final answer:
The change in the amount owed to the credit card company from returning both items is $620.
Step-by-step explanation:
To calculate the change in the amount owed to the credit card company from returning both items, you need to subtract the sum of the purchase amounts from the total refund amount. In this case, Karana's mom bought two items, one costing $236 and the other costing $384, resulting in a total purchase amount of $620. If both items were returned, the credit card company would refund the total purchase amount of $620. Therefore, the change in the amount owed to the credit card company from returning both items is $620, making option B the correct answer.