On November 14, 2018, Chase was appointed guardian over his father Patrick, due to Patrick's lack of mental capacity. On January 15, 2019, Patrick purchases a stereo system for Chase learns about the contract on February 15 , 2019. Which of the following is true?
a. The contract is void, but Chase must pay the reasonable value of the stereo.
b. The contract is void.
c. The contract is enforceable as the contract was for a necessity.
d. The contract is voidable, but Chase must pay the reasonable value of the stereo.