Ripening of fruits is hastened by using

Step 1: Analyze the question The question asks which compound speeds up (hastens) the ripening of fruits.

Step 2: The concept Ethene (C₂H₄) is a natural plant hormone. Fruits produce it as they ripen, and it triggers the changes that make fruit soft, sweet, and colourful. Because of this, ethene is used commercially to ripen fruits such as bananas, mangoes, and tomatoes. They are often harvested while still green and then exposed to ethene gas so they ripen quickly.

Step 3: Check each option

• A. Ethanol (C₂H₅OH): An alcohol used as a solvent, fuel, and in drinks. It does not ripen fruit.
• B. Ethane (C₂H₆): A saturated alkane. It is fairly unreactive and has no ripening effect.
• C. Ethene (C₂H₄): An alkene and the plant hormone that triggers ripening. ✔
• D. Ethyne (C₂H₂): An alkyne used in oxy-acetylene welding. Although it can have a similar effect in some old practices (calcium carbide, which releases ethyne, is sometimes used illegally to ripen fruit), it is not the standard ripening agent, and ethene is the correct answer.

Step 4: Answer The correct option is C. Ethene.

Tip: Remember "ethEne = ripEning", since both have the letter "e" stressed. Also remember the uses of the hydrocarbons:

• Ethene: ripening of fruits and making polythene
• Ethyne: welding
• Ethane: fuel (natural gas component)
• Ethanol: drinks, solvent, fuel