Answer:
A) firm offer rule
Step-by-step explanation:
The firm offer rule states that an offer shall remain open and firm until its expiration date (in this case a fortnight). Stelwire LLC can revoke an offer (anyone can) but in order to do so, it must notify the other party about the revocation. If Stelwire LLC didn't properly revoke the offer before Ralph accepted it, then they are liable for it.