The correct option is B. A multi cellular organisms has many cells which carry out various function and which are organised into tissues, organs and organ system. A unicellular organism on the other hand has only one cell with different cell organelles. Thus, in unicellular organisms, it is the cell organelles that carry out different functions.
B. organelles because organelles are structures in the cell for example the plasma membrane, nucleus, mitochondria, etc. which they all have their own functions to make life possible.
Related Question in Biology
- BIO 103 1) A bond is a connection between two atoms, created when atoms either share electrons to from a _____ bond. 2) A ______ bond is formed when one atom donates an electron to another atom. 3) Methane is a molecule with the chemical formula of CH4. The bonds forming this molecule are called ______? 4) A single water molecule is not commonplace. The interactions between water molecules is guided by ______bonds.