Clint Contests the Amount of a Bill He Received from Car

Clint contests the amount of a bill he received from Car Care Specialists. Under the Restatement, settlement of the claim:

A) is not valid consideration.
B) is not a legal detriment to Clint if his contentions were not made in good faith.
C) is valid consideration if at the time of the settlement the claim was doubtful because of uncertainty as to the facts.
D) does not involve a disputed debt unless Clint contests both the existence of the obligation and the amount of the bill.