Final answer:
The individual units that build all parts of the human body are called cells. Cells form tissues, tissues come together to create organs, and organs are organized into systems that help perform the body's complex functions. The correct option is c.
Step-by-step explanation:
All parts of the human body are built of individual units called cells. These cells are the basic building blocks of all organisms, including humans. A group of cells forms tissue, various tissues form an organ, and different organs make up an organ system. This organization allows for complex functions to be carried out efficiently within the body.
There are four main types of tissues in the body: epithelial tissue, connective tissue, muscle tissue, and nervous tissue. Each type is specialized for certain functions, and together, these tissues make up all the structures in the body. An organ is composed of two or more tissue types, and it performs specific physiological functions. Finally, an organ system is a group of organs that work together to perform major functions and meet the physiological needs of the body.
Hence, Option c is correct.