An example of illegal agreement is when the broker offered to list the prospective client's home if the client agreed to let him find a new home for him.
An illegal agreement refers to when a contract is agreed upon for an illegal reason where such reason are against the law.
The act of the broker in this case is seen as illegal because he is only suppose to negotiate and bargain.
Hence, the example of illegal agreement is when the broker offered to list the prospective client's home if the client agreed to let him find a new home for him.
Therefore, the Option C is correct.
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