The puffed up appearance of dough is due to production of which of the following?

CO₂ Gas .

The correct answer is Option (4) –CO₂ Gas .

The puffed-up appearance of dough is due to the production of CO₂ gas.

During the process of baking, when the dough is exposed to heat, several reactions occur. One of the key reactions is the fermentation of sugars by yeast, which produces carbon dioxide (CO₂) gas as a byproduct. The CO₂ gas gets trapped within the dough's gluten network, creating bubbles and causing the dough to rise or puff up.

The production of CO₂ gas is essential in the leavening dough, as it creates air pockets and gives the final baked product its light and airy texture. The trapped CO₂ gas expands when heated, leading to the expansion and rising of the dough.