- A Stem elongation driven by cell wall loosening at the apical meristem
- B Fruit ripening and abscission
- C Adventitious root formation at the cut ends of stem cuttings
- D Directional bending of shoots toward a unidirectional light source
Correct answer: B. Fruit ripening and abscission
Explanation: Ethylene is a gaseous hormone. It promotes fruit ripening and abscission (leaf/fruit drop).
Concept context
Phases of plant growth, the five classical plant hormones plus newer ones, photoperiodism, vernalization, and seed dormancy.