What Is the Primary Method for Measuring Damages in Contract

What is the primary method for measuring damages in contract?

A) Damages are equal to the gains the contract breaker has made from breaching the contract.
B) Damages are equal to the loss the innocent party has suffered by relying upon the contract breaker's promise to perform the contract.
C) Damages are equal to the gain the innocent party expected to obtain if the contract had been properly performed.
D) Damages are equal to a sum determined by the courts as necessary to punish the contract breaker for his breach of contract.