$25.$ Patel Engineering receives an email from a supplier, signed by the supplier's C$..$O$.$ that includes a price list for several key parts that Patel will use in a major contract. The email says the price list will be effective for thirty days. One week later, the supplier wants to withdraw the price list and raise its prices. Patel's best argument for holding the supplier to the lower prices during the thirty$-$day period is that the email was:a$.$ A Merchant's Firm Offer.b$.$ A Good Faith Offer.c$.$ An Option Contract.d$.$ A Requirements Contract.