Fruit ripening is stimulated by

The correct answer is Ethylene.

Key Points

• Fruit ripening is stimulated by Ethylene.
• It is a natural plant hormone.
• Its level in under-ripe fruit is very low, but as fruit develop, they produce larger amounts that speed up the ripening process or the stage of ripening known as the “climacteric".​

Additional Information 

• Cyto-kinin
  • It naturally works in coordination with auxins and helps in cell division and development.
• Auxin
  • It is the hormone that controls the growth of plants.
• Gibberellin
  • It is present in the meristems of apical buds and roots, young leaves, and embryo.
  • It also helps in the germination of seeds.