Answer:
The correct answer is - to protect the cells of these secretory glands from pepsin.
Explanation:
Pepsinogen is an inactive form of enzyme pepsin that is released by specific cells called chief cells within the gastric lining Releasing the inactive form of pepsin in preventing the auto-digestion of protective proteins and the cells of these secretory glands in the lining of the digestive tract.
Pepsinogen is activated by acidic pH to pepsin of the stomach lumen and the cell lining of the stomach is protected by mucus lining.