Yeast is used for the production of the following :

Correct option is B

The correct answer is (b).
Explanation
Yeast carries out fermentation, a biological process in which sugars are converted into alcohol and carbon dioxide in the absence of oxygen. This process is widely used in baking and brewing industries.
Additional Information
• Option {a} is incorrect because yeast consumes sugar rather than producing it. • Option {c} is incorrect because hydrochloric acid is not produced biologically by yeast. • Option {d} is incorrect because oxygen is not produced during fermentation.