Which factor is most closely associated with successful smoking cessation?

Correct Answer: C

Rationale: Successful smoking cessation is strongly tied to planning for relapses (e.g., identifying triggers and coping strategies), as it addresses the chronic nature of addiction. Support groups (A) help but are less critical, and B and D ignore the need for comprehensive approaches.

Correct Answer: C

Rationale: The 'lub-dub' sound corresponds to the closing of heart valves during the cardiac cycle. The 'lub' is the closing of the atrioventricular valves (mitral and tricuspid) at the start of systole, preventing backflow into the atria. The 'dub' is the closing of the semilunar valves (aortic and pulmonary) at the end of systole. Choices A and B are partial truths, but the full sequence involves both valve types. Choices C and D refer to muscle actions, not the sound’s direct cause.

Correct Answer: D

Rationale: The correct anatomical nesting is heart (the organ), surrounded by the pericardial sac (its protective layers), within the mediastinum (central thoracic region), all enclosed in the thoracic cavity. The pleural space relates to the lungs, not the heart directly.

Correct Answer: C

Rationale: Systole refers to the phase of the cardiac cycle when the ventricles contract to pump blood into the pulmonary artery and aorta. Ventricular filling and atrial relaxation occur during diastole, while atrial filling happens throughout the cycle but is not specific to systole.

Correct Answer: A

Rationale: Pulse pressure is systolic pressure minus diastolic pressure: 135 - 75 = 60 mmHg. This reflects the force of ventricular ejection.