LIFE SCIENCE

Detailed explanation-1: -Cell is the smallest structural and functional unit of an organism. Each cell of an organism performs functions such as nutrition, transport, excretion and reproduction.

Detailed explanation-2: -Answer and Explanation: The smallest living unit within the human body is B) a cell. In fact, this is true for all biological life. The cell is the smallest functional unit that could theoretically survive and reproduce if it was isolated from the rest of the body.

Detailed explanation-3: -A cell is the smallest unit that is typically considered alive and is a fundamental unit of life. All living organisms are composed of cells, from just one (unicellular) to many trillions (multicellular). Cell biology is the study of cells, their physiology, structure, and life cycle.

Detailed explanation-4: -A cell is the smallest independently functioning unit of a living organism.