Li Cheung, a 55-year-old male, is admitted for observation to a hospital following an episode of severe chest pain. His symptoms include substernal chest pain, reflux heartburn, feeling of fullness, sore throat, and hoarseness. Li Cheung is diagnosed with a hiatal hernia, gastric ulcer, and gastroesophageal reflux disease (GERD). He will need instructions about his new regime, which includes taking Maalox, simethicone, and Prevacid as well as changes in his diet and lifestyle management. What should Li be told about simethicone? a. It consists of living organisms that can alter intestinal flora in a positive way. b. It decreases gastric motility. c. It has a direct, protective effect on intestinal mucosa. d. It helps break up gas bubbles in the digestive tract.