单选题 When preparing a client for a scheduled colonoscopy, which of the following nursing interventions would the nurse include?
A. Inserting a nasogastric tube 12 hours before the procedure.
B. Cleansing the bowel with laxatives or enemas.
C. Administering an antibiotic to decrease the risk of infection.
D. Spraying a local anesthetic into the client's throat to calm the gag reflex.

【正确答案】 B

【答案解析】A colonoscopy is the visual examination of the large bowel using a fiberoptic endoscope inserted into the client's rectum. Typically the client will be placed on a liquid diet 24 hours before the procedure and kept NPO after midnight the night before the procedure. The bowel is cleansed through the use of laxatives and enemas.