Final answer:
The written contract establishes a legally binding agreement between Alex and Simone.
Step-by-step explanation:
In this situation, the correct option is c) The written contract establishes a legally binding agreement between Alex and Simone.
A written contract is a legally binding agreement between two or more parties that outlines the terms and conditions of their agreement.
By presenting Simone with a written contract, Alex and Simone have entered into a legally binding agreement for the lawn care services.
It's important to note that the legality of a contract is not dependent on the age of the individuals involved. Therefore, parental consent (option d) is not required for the contract to be valid.