Answer: C. She should observe female sea turtles making nests in their natural habitats.
Step-by-step explanation:
A scientific investigation is a scientific inquiry which deals with answering the queries of the natural process, phenomena or events. The answers are supported by direct observation and detail and valid experimentation procedures. The outcomes are valid and acceptable.
C. is the correct option this is because of the fact that it involves the direct observation of sea turtles making nests. This will be valid outcome of the scientific investigation.