When a neurologist asks a patient to smile, which cranial nerve is being tested?

Correct Answer: C

Rationale: Step-by-step rationale: 1. The cranial nerve responsible for facial expression is CN VII, the facial nerve. 2. When a neurologist asks a patient to smile, they are testing the function of CN VII. 3. CN II (optic nerve) is responsible for vision, not facial expression. 4. CN X (vagus nerve) is responsible for various functions like heart rate and digestion, not facial expression. 5. CN XI (accessory nerve) is responsible for shoulder movement, not facial expression. Summary: Testing a patient's ability to smile involves assessing the function of CN VII, the facial nerve. Choices A, B, and D are incorrect as they are associated with different functions and not responsible for controlling facial muscles.

Correct Answer: D

Rationale: The correct answer is D because Huntington's disease is a neurodegenerative disorder that presents with a triad of symptoms: abnormal involuntary movements (chorea), intellectual decline, and emotional disturbances. Chorea is a hallmark feature of Huntington's disease, caused by damage to the basal ganglia. Intellectual decline includes cognitive impairments such as memory loss and executive dysfunction. Emotional disturbances involve mood swings, irritability, and apathy. Therefore, all three manifestations are commonly seen in individuals with Huntington's disease, making D the correct choice. Choices A, B, and C are incorrect individually because they do not encompass all the key clinical features of Huntington's disease.

Correct Answer: C

Rationale: The correct answer is C because in myasthenia gravis, which is characterized by muscle weakness and fatigue, the administration of edrophonium will temporarily improve muscle strength due to increased availability of acetylcholine at the neuromuscular junction. This improvement should be noted within 30 to 60 seconds after the administration of the medication. Choice A is incorrect because joint pain is not a typical response to edrophonium in the context of myasthenia gravis. Choice B is incorrect because feelings of faintness, dizziness, hypotension, and flushing are more indicative of a cholinergic crisis, which occurs when too much edrophonium is administered. Choice D is incorrect because an increase in muscle strength post-edrophonium administration would not be expected in a client with myasthenia gravis.

Correct Answer: A

Rationale: The correct answer is A. In the Snellen eye chart test, the first number (20) represents the distance at which the client is viewing the chart, and the second number (40) represents the distance at which a person with normal vision can read the same line. Therefore, a client with 20/40 vision sees letters at 20 feet that others with normal vision can read at 40 feet. Choices B, C, and D are incorrect because they do not accurately reflect the interpretation of the 20/40 vision result from the Snellen eye chart test. B is incorrect because the client does not see letters at 40 feet that others can read at 20 feet. Choices C and D are incorrect because the Snellen eye chart test measures visual acuity, not color perception.

Correct Answer: A

Rationale: The correct answer is A because successful treatment of diabetes insipidus aims to reduce excessive urine output and dehydration. A fluid intake of less than 2,500mL in 24 hours indicates proper control of fluid balance. Choice B is incorrect because urine output of more than 200mL/hour suggests ongoing excessive fluid loss, which is not indicative of successful treatment. Choice C is incorrect as a blood pressure of 90/50mmHg is low and may indicate hypotension, which is not a specific indicator of successful diabetes insipidus treatment. Choice D is incorrect because a pulse rate of 126 beats/min is not a direct marker of diabetes insipidus treatment success. In summary, the correct indicator of successful treatment of diabetes insipidus is a reduction in fluid intake, option A, as it signifies improved fluid balance and hydration status.