Answer: A. They had a unilateral. express agreement.
Step-by-step explanation:
A Unilateral Express Contract or Agreement is one where the Offeror expressly promises to pay the person executing the contract after the occurence of the specified activity. The is what Debbie did when she said that the first person to mow her yard would get $50. Meaning she was expressly offering $50 for her yard to be mowed.
Such contracts are usually an open request in which one is willing to pay for a specified act not unlike what Debby did when she told the CLASS that the first person to mow would get $50.
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