Concept:Termination by performance occurs when every party has fully discharged its contractual duties.
Explanation:Performance means completing the terms and conditions of the contract exactly as agreed.
When all parties have fulfilled their obligations, the contract is fully executed and comes to an end.
This is different from breach, which is a failure to perform.
It is also different from frustration, which is an outside event making performance impossible.
It is not operation of the law, because the termination results from the parties’ own acts.
Answer:A. performance