A nurse is caring for a client who has a prescription for a stool test for guaiac. The nurse understands the purpose of the test is to check the stool for which of the following substances?

A. A guaiac test does not check for parasites. Tests for parasites typically involve microscopic examination of the stool or other specialized tests. B. Steatorrhea refers to fat in the stool, and this is detected through tests that measure fat content in the stool, not a guaiac test. C. A guaiac test is specifically used to detect occult (hidden) blood in the stool, which can indicate gastrointestinal bleeding, polyps, or colorectal cancer. D. Bacteria in the stool is detected through stool cultures, not a guaiac test.