What is required for a merchant offer to be irrevocable according to the Merchant Firm Offer Rule?

For a merchant offer to be considered irrevocable under the Merchant Firm Offer Rule, it indeed needs to be signed by the merchant offeror. This rule, established under the Uniform Commercial Code (UCC), governs offers made by merchants concerning the sale of goods. A merchant's offer can be made irrevocable if it meets certain criteria, one of which is that it must be in writing and signed by the merchant.

The requirement of a signature serves to provide a clear indication of the merchant's intention to be bound by the offer, effectively preventing the offeror from revoking the offer before the stated time period has elapsed, as long as the period is not exceeding three months.

While the other choices involve aspects of communication or timeframes, they do not address the fundamental requirement necessary to establish an irrevocable offer. Therefore, it is the signed writing by the merchant that solidifies the offer's irrevocability under the Merchant Firm Offer Rule.