The cells in the colony respond to stimuli separately. The cells in the colony are arranged in a specific shape. Some cells in the colony are specialized for reproduction. Cells in the colony are connected by strands of cytoplasm.
I gave my students this multiple choice question: Which characteristic of a volvox colony makes it more like a multicellular organism than a simple cluster of unicellular organisms?

Only one answer is correct among these 4 choices:
- The cells in the colony respond to stimuli separately.
- The cells in the colony are arranged in a specific shape.
- Some cells in the colony are specialized for reproduction.
- Cells in the colony are connected by strands of cytoplasm.

Could you tell me which one is correct?

Some cells in the colony are specialized for reproduction.