Question

complex systems have many subsystems, layers of control, and __________ loops.
closed
open
inputs
feedback

Explanation:

Complex systems often have feedback loops which help in regulating and controlling the system's behavior based on the output or results. Closed - open are types of control systems but not the most general term for loops in complex systems. Inputs are not loops. Feedback loops are a fundamental concept in complex systems.

Answer:

D. feedback