What is the term for a group of cells that work together to perform a specific function?

The correct answer is "tissue." A tissue is defined as a group of cells that are similar in structure and work together to carry out a specific function within an organism. Tissues serve as the building blocks for organs, which consist of multiple types of tissues working together to perform more complex functions.

In the context of the human body, for instance, muscle tissue is responsible for movement, while nervous tissue is essential for transmitting signals throughout the body. This distinction highlights the role of tissue as a foundational biological concept, indicating how cells can collaborate to support larger structures and functions in an organism's anatomy and physiology. Understanding this concept is crucial for grasping more advanced topics in biology and health sciences.