Which finding indicates an antacid produced a therapeutic effect?

A. Decreased gastric pH: Antacids work by neutralizing stomach acid, which actually raises gastric pH rather than lowering it. A decrease in pH would indicate more acidity, which is contrary to the desired effect. B. Relief of heartburn: Heartburn is caused by gastric acid irritating the esophagus. Symptom relief demonstrates that the antacid has effectively neutralized excess stomach acid and provided the intended therapeutic effect. C. Harder stools: While some antacids containing aluminum can cause constipation, this is a side effect rather than a therapeutic outcome. Stool consistency does not reflect acid neutralization or heartburn relief. D. Elevated calcium: Calcium-containing antacids may increase serum calcium if overused, but this is a potential adverse effect, not an indicator that gastric symptoms have been alleviated.