A nurse is assessing a client who has a urinary tract infection and is receiving cefacior. The nurse should monitor the client for which of the following adverse effects of the medication?

A. Blurred vision: Blurred vision is not a common adverse effect of cefaclor. Visual disturbances are typically unrelated to cephalosporin therapy, so monitoring for this symptom is not a priority during treatment. B. Diarrhea: Diarrhea is a known adverse effect of cefaclor due to its impact on gut flora, which can lead to mild gastrointestinal upset or, in severe cases, antibiotic-associated colitis. Monitoring for changes in bowel patterns helps detect complications early and guide intervention. C. Hypoglycemia: Hypoglycemia is not typically associated with cefaclor use. Cephalosporins do not directly affect blood glucose regulation, so routine glucose monitoring is not required unless the client has other risk factors, such as concurrent insulin therapy. D. Photosensitivity: While some antibiotics (like tetracyclines or fluoroquinolones) can cause photosensitivity, it is not a primary or common adverse effect of cefaclor.