Final answer:
A group of organs that perform one or more vital functions for the body is called a(n organ system. The correct answer is d. system.
Step-by-step explanation:
An organ system is a group of organs that work together to perform major functions or meet physiological needs of the body. In the human body, organs such as the heart, lungs, and kidneys are part of different organ systems.
For example, the circulatory system consists of the heart, blood vessels, and blood. The heart pumps blood through the blood vessels to deliver oxygen and nutrients to all parts of the body. The respiratory system, on the other hand, includes the lungs and airways, which help in the exchange of oxygen and carbon dioxide.
Each organ in an organ system has a specific role and contributes to the overall functioning of the body. Therefore the correct answer is d. system.