The correct statement about multicellular organisms is: A multicellular organism has many specialized cells.
In multicellular organisms, cells often differentiate to perform specific functions, leading to specialization, such as muscle cells for movement, nerve cells for signal transmission, and epithelial cells for protection and absorption. The other statements are incorrect: multicellular organisms do not typically reproduce through binary fission, not all cells must perform all life functions (as specialization allows for division of labor), and not every cell is responsible for movement.