A paper supply company ran an advertisement offering rolls of cash register tape for sale for $10 a roll, minimum purchase of 100 rolls. In response to the advertisement, an office supply retailer sent a written order to the paper supply company for 150 rolls of register tape. In the letter that accompanied the retailer's order, the retailer stated that it would send the paper supply company payment of $1,500 upon delivery. The letter also stated that the register tape must be compatible with three specified commonly used cash register models.

The day after receiving the written order and letter from the retailer, the paper supply company shipped 150 rolls of register tape to the retailer. Accompanying the invoice was a letter from the paper supply company stating that the register tape is compatible with two of the specified models of cash register, but that the retailer makes no warranties as to the compatibility of the register tape with any other model of cash register. Shortly after accepting shipment of the register tape, the retailer realized that the register tape did not fit onto the third model of cash register that it had specified and instituted an action against the paper supply company.

Which of the following statements would offer the strongest support in favor of the retailer's position?

A. The retailer's letter was an offer, and shipment of the register tape was an acceptance.

B. The retailer's letter was an offer, and the paper supply company's letter accompanying the invoice was an acceptance.

C. The paper supply company's letter was an offer, and acceptance of the register tape by the retailer was an acceptance of the offer.

D. Shipment of the register tape was a counteroffer, and acceptance of the register tape by the retailer was an acceptance of the counteroffer.