Final answer:
Chief cells of the gastric mucosa secrete pepsinogen, which is the inactive form of the enzyme pepsin, required for protein digestion in the stomach. The correct answer to the question is (c) pepsinogen.
Step-by-step explanation:
The chief cells of the gastric mucosa have a specific role in the digestion process. These cells are located mainly in the bottom regions of the gastric glands and their principal function is to secrete pepsinogen, which is an inactive precursor to the enzyme pepsin.
Pepsin is essential for the breakdown of proteins into peptides during digestion. It's important to note that pepsinogen itself is not active; it requires the acidic environment provided by hydrochloric acid (HCl), secreted by the parietal cells of the stomach, to be converted into active pepsin.
Given the options provided: (a) glucagon, (b) HCl, (c) pepsinogen, (d) bile, and (e) gastrin, the correct option that the chief cells secrete is pepsinogen. Other cells in the stomach produce the remaining substances: parietal cells secrete HCl, endocrine G cells produce gastrin, and bile is secreted by the liver, not the stomach. Therefore, please provide the correct option which, in this case, is (c) pepsinogen.