Final answer:
The sensor in the model presented is option (D) Sensor. It's a device that responds to physical input from the environment, distinguishing it from other components like the CPU, RAM, and hard drive. Hard drives generally consume a notable amount of power due to their mechanical parts.
Step-by-step explanation:
When considering the components of a computer model and trying to identify the sensors, the correct answer would be (D) Sensor. Sensors in technological devices are typically used to detect events or changes in the environment and send the information to other electronics, usually a processor.
The CPU (A) is the central processing unit and acts as the brain of the computer, processing instructions. RAM (B) stands for Random Access Memory, which temporarily stores data for quick access while a computer is running. The hard drive (C) is the data storage device that uses magnetic storage to store and retrieve digital information. However, none of these components are sensors, which detect and respond to some type of input from the physical environment.
Regarding the question on power consumption, a device like a hard drive, especially traditional mechanical ones, may consume a significant amount of power when it is on/running. This is due to the movement of mechanical parts such as the spinning disks and moving read/write heads.