Answer:
B. mitochondria to do cellular respiration.
Step-by-step explanation:
A cell can be defined as the fundamental or basic functional, structural and smallest unit of life for all living organisms. Some living organisms are unicellular while others are multicellular in nature.
A unicellular organism refers to a living organism that possess a single-cell while a multicellular organism has many (multiple) cells.
All living organisms need energy to function. Both unicellular organisms and multicellular organism retrieve energy using mitochondria to do cellular respiration.
Basically, mitochondria is one of the cell organelles found in all living organisms and it is known as the powerhouse. Therefore, mitochondria provides all the energy required in the cell by transforming energy forms through series of chemical reactions; breaking down of glucose into Adenosine Triphosphate (ATP) used for providing energy for cellular activities in the body of living organisms.