Final answer:
The correct answer is caffeic acid, which is a compound with a molar mass of 180.16 g/mol found in the Native American stomachache remedy from common chokecherry.
Step-by-step explanation:
The ingredient in the Native American stomachache remedy derived from common chokecherry that the question refers to is caffeic acid. This component has a molar mass of 180.16 g/mol and should not be confused with acetic acid, caffeine, lactic acid, or sulfuric acid, which are distinctly different compounds.
Caffeic acid is known for its presence in many plants and has been used traditionally for its potential health benefits, although it is not the same as the mechanisms provided by antacids like calcium carbonate or pain-relief agents like acetylsalicylic acid (aspirin).