Concept:A pro forma invoice is an advance bill sent to a buyer before goods are delivered.Explanation:It acts as a written quotation or preliminary invoice.It informs the buyer about the cost and other sales terms before delivery.This helps the buyer confirm the price and avoid disputes after the goods arrive.The seller uses it to state clearly what the buyer is expected to pay.Answer:It is sent to inform a buyer about the price of goods.So, the correct option is B.