Explanation
The technician would use a Return Order to create a return for the unused circuit board. The Return Order would specify the quantity of the product being returned, the reason for the return, and the shipping address.
The technician would then use a Product Receipt to record the receipt of the returned product. The Product Receipt would specify the quantity of the product received, the condition of the product, and the location of the product.
The other two options are incorrect because they are not used to return products. A Work Order is used to track the work that needs to be done on a product or service. A Product Transfer is used to move products from one location to another.