What is the structural and functional unit of living organisms?

Explanation-

In the year 1665, Robert Hooke discovered cells from the bark of the Spanish Oaktree, he remarked the structure as small compartments which are hollow from the inside, actually he discovered dead plant cells.
Cells are the structural and functional unit of a living organism, all living organisms are made up of cells.
Cells perform all the vital functions of the living organism that is needed for survival.

Tissue- Group of the similar or dissimilar cells, having a common origin grouped to perform a specific function.

Organ-Tissues with similar functions are grouped to form an organ.


Final Answer-

So, The correct option is B.