Final answer:
A nurse should expect to find ketones in the urine when assessing a client with gestational diabetes mellitus experiencing hyperglycemia because high blood glucose can result in the production of ketone bodies.
Step-by-step explanation:
A nurse assessing a client who has gestational diabetes mellitus and is experiencing hyperglycemia should expect to find ketones in the urine. Hyperglycemia occurs when there is a high level of glucose in the blood, and this can lead to the release of fatty acids and the overproduction of ketone bodies, resulting in ketoacidosis. Excess glucose in the blood can exceed the reabsorption capacity of the kidneys, leading to glucose in the urine. Additionally, high glucose levels can lead to increased urine production and a risk of dehydration. Therefore, the correct answer to which finding the nurse should expect is c. Ketones in the urine.