Which rule requires that the terms of acceptance match exactly the terms of an offer?

The Mirror Image Rule is the correct answer as it states that for a contract to be formed, the acceptance must exactly match the terms of the offer presented. This means that any deviation or change in the terms during acceptance modifies the original offer and constitutes a counteroffer rather than an acceptance.

This rule is fundamental in contract law, establishing that a valid acceptance cannot introduce additional terms or alter the existing terms of the offer. The necessity for a "mirror image" ensures both parties have a clear understanding of their rights and obligations, thereby reducing potential disputes later.

The other options refer to different concepts within the realm of contract law. The Substantial Performance Rule pertains to situations involving contract performance where minor deviations are acceptable as long as the essential purpose of the contract is fulfilled. The Offer and Acceptance Rule is more of a general principle that outlines the necessity of an offer being made and accepted, without specifying the exact matching requirement of the Mirror Image Rule. The Contract Validity Rule, while it addresses the overall enforceability of contracts, does not specifically concern the precise matching of acceptance with the offer's terms.