Answer:
The correct answer is option B. "organ systems, organs, tissues, cells".
Explanation:
The biological processes that sustain life in the human body take place at different structural organizations. The simplest being the chemical processes themselves, and the most complex the organ systems. However, without including the chemical processes, the correct order from most complex to simplest is: organ systems, organs, tissues, cells. Cells are the basics units of life, tissues are groups of cells that function as an unit (epithelial, connective, muscular, among others), organs are made of one or more tissues (heart, lungs, liver, among others) and organ systems are comprised of multiple tissues performing a body function ( nervous, circulatory, respiratory, among others).