Question

The process of conversion of sugar into alcohol is called
(i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection

NCERT Class VIII
Science - Main Course Book

Chapter 2. Microorganisms: Friend and Foe

Answer 1

The process of converting of sugar into alcohol is called fermentation. Ethanol Fermentation, also called Alcoholic Fermentation, is a biological process which converts sugars such as glucose, fructose and sucrose into cellular energy, producing ethanol and carbon dioxide as a side effect. As yeast performs this conversion in the absence of oxygen, alcoholic fermentation is considered an anaerobic process.

Ethanol fermentation has many uses, including the production of alcoholic beverages, the production of ethanol fuel, and bread baking.
Wine is produced by fermentation of the natural sugars present in grapes. Cider and perry are produced by similar fermentation of natural sugars in apples and pears respectively. Beer, Whiskey and vodka are produced by fermentation of grain starches that have been converted to sugar by the enzyme amylase, which is present in grain kernels that have been malted. Rum and some other beverages are produced by fermentation and distillation of sugarcane.

So, the option (3) is correct.

Answer 2

Simple

The process of conversion of sugar into alcohol is fermentation