Under the mailbox rule, when is an acceptance effective, assuming reasonable means of communication and no contrary language in the offer?

Under the mailbox rule, when is an acceptance effective, assuming reasonable means of communication and no contrary language in the offer?

• A. Acceptance is effective only when the offeror receives it.
• B. Acceptance is effective on receipt by the offeror.
• C. Acceptance is effective when the offeree communicates by instant messenger.
• D. Under the mailbox rule, acceptance is effective on dispatch when sent by reasonable means, unless the offer specifies otherwise.

Answer: (D)