Final answer:
The nurse's correct interpretation of a high percentage of blast cells and promyelocytes in the blood of a client with chronic myelogenous leukemia is that the disease has become more aggressive.
Step-by-step explanation:
The nurse's correct interpretation of a high percentage of blast cells and promyelocytes in the blood of a client with chronic myelogenous leukemia is that the disease has become more aggressive. Chronic myelogenous leukemia is characterized by an overproduction of young, immature leukocytes, and an increase in blast cells and promyelocytes indicates an escalation of the disease. This can lead to a higher risk of complications and worsening of symptoms.