I believe that would be C.
A noise that produces an echo when it bounces off a distant wall.
The correct answer in the space provided is state. He is likely studying the state of consciousness, it is because the state of consciousness covers the awareness of a person that occurs in his or her daily life. An example of it is when a person is walking, dreaming, eating in which occurs in their everyday life.
Answer:
A. Enforcing state laws
Explanation:
B and C is the legislative branch, congress revises the constitution and changes other laws or legislature. D is the judicial branch, they make decisions in court and make judgments.