Celine hears that Chad is selling his car to the first person who shows up with $1,000 to purchase it. Celine calls Chad and says she will come tomorrow to look at the car. Chad acknowledges that he will be home. When Celine shows up, she is surprised to learn that Chad sold the car to Ellie, who brought Chad $1,000 in cash for the car shortly after Celine's call. He signed over the title and gave Ellie the keys. What kind of contract did Chad make with Ellie?

Group of answer choices

A unilateral contract that she performed by an act

A bilateral contract that she performed by a promise

A void contract, he should have sold the car to Celine because she called first

An executory contract