The correct answer is B. Magnesium hydroxide.
Antacids are commonly used to get rid of acidity in the stomach. They work by neutralizing stomach acid. Magnesium hydroxide is a common antacid that is available over-the-counter. It is a white, odorless powder that is mixed with water to form a suspension. Magnesium hydroxide is effective in relieving heartburn, indigestion, and sour stomach. It is also used to treat constipation.
Sodium hydrogen phthalate is a white, odorless powder that is used as a food additive. It is also used in the manufacture of plastics and other chemicals. Sodium hydrogen phthalate is not an antacid.
Calcium hydroxide is a white, odorless powder that is used as a building material and in the manufacture of cement. Calcium hydroxide is not an antacid.
Manganese acetate is a white, odorless powder that is used as a food additive and in the manufacture of batteries. Manganese acetate is not an antacid.