Answer:
A) The offer was probably still open the next day because a reasonable length of time would not have expired.
Step-by-step explanation:
If we consider that Keegan's revocation was ineffective (which I believe was effective), then Oberon would usually have between 1 to 2 days to consider and respond to Keegan's offer. Since no time limit was specified, we have to consider reasonable lengths of time and 1 or 2 days is generally considered reasonable in different states. Whether 1 day or 2 days is the time set by state law doesn't matter in this case since not even 1 day had passed.