Final answer:
A WBC count of 2,800 is a contraindication for a client with schizophrenia to start taking clozapine due to the risk of agranulocytosis.
Step-by-step explanation:
A student has inquired about a contraindication for taking clozapine for a client with schizophrenia. Among the listed options, a WBC count of 2,800 is a significant finding that indicates a potential contraindication. Clozapine can lead to agranulocytosis, a potentially life-threatening reduction in white blood cells (WBCs). Therefore, a client with a WBC count of 2,800—which is below the normal range—should not begin treatment with clozapine due to the increased risk of infection and compromised immune response.