Correct Answer: D

Rationale: Hypertension is the correct answer. Hypertension can cause damage to blood vessels, increasing the risk of blood clots forming, which can potentially lead to a stroke. Aneurysm is a localized, abnormal dilation of a blood vessel that can lead to complications but does not directly cause blood clots and strokes. Arrhythmia refers to irregular heart rhythms and is not directly linked to the formation of blood clots. Asthma is a chronic respiratory condition and does not typically lead to blood clots and strokes.

Correct Answer: C

Rationale: The correct answer is C: GABA (gamma-aminobutyric acid). GABA is an inhibitory neurotransmitter that slows down neuronal activity, helping to prevent overexcitation in the brain. It counterbalances the effects of excitatory neurotransmitters like glutamate, playing a crucial role in maintaining the balance of neuronal activity in the brain. Acetylcholine (Choice A) is primarily an excitatory neurotransmitter involved in muscle movement and cognitive functions. Dopamine (Choice B) plays a role in reward-motivated behavior and motor control. Serotonin (Choice D) is involved in regulating mood, appetite, and sleep but is not primarily responsible for slowing down neuronal activity to prevent overexcitation.

Correct Answer: B

Rationale: The correct answer is B: Kidneys. The kidneys are responsible for filtering waste from the blood and maintaining electrolyte balance. They help regulate the body's fluid levels and produce urine as a means of waste elimination. The liver primarily plays a role in detoxification and metabolism, not in maintaining electrolyte balance or filtering waste from the blood. The heart is responsible for pumping blood, not for electrolyte balance or waste filtration. The lungs are primarily involved in gas exchange, not in maintaining electrolyte balance or filtering waste from the blood.

Correct Answer: B

Rationale: Bronchitis is the correct answer. It is the inflammation of the bronchi, which are the air passages in the lungs. Bronchitis typically presents with symptoms such as a persistent cough, mucus production, and sometimes difficulty breathing. Pneumonia, on the other hand, is an infection that causes inflammation in the air sacs of the lungs, not specifically the bronchi. Emphysema is a chronic lung condition characterized by the gradual destruction of the air sacs in the lungs, resulting in breathing difficulties. Pleurisy refers to inflammation of the pleura, the lining around the lungs and chest cavity, causing chest pain when breathing or coughing.

Correct Answer: B

Rationale: The correct answer is a Pivot joint. A pivot joint, like the joint in the neck, enables rotational movement around a single axis. This type of joint is crucial for allowing the head to turn from side to side. Choice A, Ball-and-socket joint, allows for movement in multiple axes due to its spherical structure, not limited to single-axis rotation. Choice C, Hinge joint, allows movement in one plane like a door hinge, but not rotational movement around a single axis. Choice D, Saddle joint, allows movement in multiple directions but is not specifically designed for rotational movement around a single axis.