Question

Useful microorganisms in our lives are

• A. Lactobacillus
• B. Salmonella
• C. Yeast
• D. Both A and C

Answer 1

Answer: (D)

Both A and C

Lactobacillus is a bacterium which can convert lactose sugar of milk to lactic acid and in turn forms curd.
Yeast is used as leavening agent in bread making. Yeast converts sugar present in the dough to carbon dioxide. Due to this, dough expands. When such dough is baked then air pockets formed due to carbon dioxide which gives soft and spongy texture to the bread.
Typhoid is caused by Salmonella typhi which is a bacteria. Hence, it is not a useful microorganism.

Thus, the correct answer is option D.