An antacid tablet added to a glass of water fizzes and bubbles as it mixes.

Which of the indicators of a chemical change is represented in this scenario?

formation of a gas
change in color
change in energy
formation of a precipitate
is it the last one?

for anyone in the future it is: formation of gas

i believe its d, but i'm not fully sure.

it was wrong i think it is the first one

The fizzing and bubbling indicates generation of a gas.

Baking soda and vinegar will do it big time. You can use it to clear clogged drains but do not stick your face near the reaction.

Yes, the indicator of a chemical change that is represented in this scenario is the formation of a gas.