Which statement best describes the core principles of classical cell theory in the history of cell biology?

• A. Only multicellular organisms are made of cells, while unicellular organisms are not considered living.
• B. Cells originate spontaneously from nonliving matter under the right environmental conditions.
• C. All living organisms are composed of one or more cells, the cell is the basic unit of life, and all cells arise from pre-existing cells.
• D. All cells contain a membrane-bound nucleus, and new cells form only by budding from the nucleus.

Answer: (C)

Verified step by step guidance

1. Step 1: Understand that classical cell theory is a foundational concept in cell biology that explains the nature and origin of cells in living organisms.
2. Step 2: Recall the three core principles of classical cell theory: (1) All living organisms are composed of one or more cells, (2) The cell is the basic unit of structure and function in living organisms, and (3) All cells arise from pre-existing cells.
3. Step 3: Evaluate each statement in the problem by comparing it to these core principles to determine which one accurately reflects the classical cell theory.
4. Step 4: Recognize that statements suggesting spontaneous generation or limiting life to only multicellular organisms contradict the established principles of cell theory.
5. Step 5: Conclude that the statement summarizing all living organisms being made of cells, the cell as the basic unit of life, and cells arising from pre-existing cells best describes the core principles of classical cell theory.