Which of the following is/are TRUE about performance of a contract?
A. Under the UCC, the performance of a sales contract must meet the "perfect tender" rule.
B. Under the common law, the performance of a construction contract must meet the "substantial performance" doctrine.
C. Under the common law, a contract with a time for performance must be performed as a general rule on the contract date or a reasonable time thereafter.
D. All of the above are true.