Final answer:
The nurse's effective statement is option C, which accurately explains the process of reconstitution in parental drug administration.
Step-by-step explanation:
The statement by the nurse that indicates effective teaching is option C: "Reconstitution is the process of adding liquid, known as diluent, to a powdered substance."
This statement accurately explains the process of reconstitution, which is a common practice in parental drug administration. When a medication is in a powdered form, it needs to be mixed with a liquid (the diluent) to form a solution that can be administered intravenously or via other parental routes.
By mentioning this process, the nurse demonstrates a good understanding of reconstitution, which is an essential skill in drug administration.