Li Jang agrees to sell ten shares of Black Bear Corporation stock to Pam. Neither party knows whether the stock will increase or decrease in value. Pam believes that it will increase in value. If she is mistaken, her mistake will

a$.$ justify voiding the contract.

b$.$ not justify voiding the contract.

c$.$ justify a refund to her from Li Jang of the difference.

d$.$ justify a payment from her to Li Jang of the difference.