Which procedure provides visual examination of the sigmoid colon?

• A. Thoracoscopy
• B. Technetium Tc-99m
• C. Skin Biopsy
• D. Sigmoidoscopy

Answer: (D)

Visual examination of the sigmoid colon is done with sigmoidoscopy. A sigmoidoscope is inserted through the anus to inspect the mucosa of the distal colon, typically reaching the sigmoid colon and sometimes the descending colon. This allows direct visualization of the lining to identify abnormalities such as inflammation, polyps, or sources of bleeding, and it often enables targeted biopsies or minor interventions. The other options correspond to different areas or purposes: thoracoscopy examines the chest cavity, Technetium Tc-99m is a radioactive tracer used in nuclear imaging, and a skin biopsy samples skin tissue. Thus, sigmoidoscopy is the procedure that provides a visual exam of the sigmoid colon.