(Answered) : Assume that a car owner contracts with a mechanic to have his engine overhauled. The mechanic mistakenly used original equipment

Assume that a car owner contracts with a mechanic to have his engine overhauled. The mechanic mistakenly used original equipment quality piston rings in doing the overhaul, whereas the
contract had called for the use of premium quality rings that are better than original equipment
quality. Assume that the rings used by the mechanic should not affect the performance of the car.

Which of the following is true?
A) This is a substantial performance, and the owner must still pay something to the mechanic.

B) This is a novation, and the owner owes nothing to the mechanic.
C) This is a substantial performance, and the owner