Answer:
C. not valid because performance depends on Parsley's personal skills
Explanation:
A valid contract refers to an agreement entered into by parties which legally binds both parties and is enforceable under the law.
For a contract to be termed as valid, it must be performed by the parties to it.
Performance clause in a valid contract refers to doing or acting in a way as is required by the terms of the contract.
In the given case, Parsley signed a contract to provide services i.e provide French cooking lessons to Curry. Later, Parsley wants to transfer his duties to Relish.
The transfer will not be valid since the performance i.e service to be provided by Parsley are of personal nature and the consideration is based upon that. No two individuals can provide exact services.