What is the basic unit of life?

• A. Organ
• B. Tissue
• C. Cell
• D. System

Answer: (C)

The basic unit of life is the cell. Cells are the smallest structural and functional units of an organism, and they are often referred to as the building blocks of life. Each cell performs essential life processes, such as metabolism, energy production, and reproduction.

In multicellular organisms, cells group together to form tissues, which then combine to form organs, and these organs work together as systems. However, none of these higher levels of organization—organ, tissue, or system—can function independently and require the cellular level as their foundation. Thus, the cell is recognized as the fundamental unit of both structure and function in living organisms.