The nurse is performing an assessment of the clients lungs. The nurse recognizes that the left lung:

A. Fifth left intercostal space at the midclavicular line:

Explanation: The apical pulse, or the point of maximal impulse (PMI), is typically located at the fifth intercostal space at the midclavicular line on the chest. This is the area where the heartbeat is best heard using a stethoscope in most adults.

B. Third left intercostal space at the midclavicular line:

Explanation: This location is too high for the apical pulse. The heart's apex is generally not found at the third intercostal space; it's lower, closer to the fifth intercostal space.

C. Fourth left intercostal space at the sternal border:

Explanation: This location is not the typical site for auscultating the apical pulse. The PMI is usually heard at the midclavicular line, not at the sternal border.

D. Under the left breast at the midclavicular line:

Explanation: This position is not precise enough for auscultating the apical pulse. The specific intercostal space (fifth) and midclavicular line are crucial for accurate assessment.

A. Wheezing: Wheezing is a continuous, high-pitched whistling sound usually heard during expiration. It is often associated with narrowed airways, such as in asthma or chronic obstructive pulmonary disease (COPD). Wheezing occurs due to the turbulent airflow through narrowed bronchi or bronchioles and is not typically associated with pleuritis.

B. Friction rub: Pleuritis, or inflammation of the pleura, can cause a friction rub. This sound occurs when the inflamed pleural layers rub against each other during breathing. It's a grating or rubbing sound heard on auscultation and is a hallmark sign of pleuritis.

C. Stridor: Stridor is a high-pitched, harsh sound heard during inspiration and sometimes expiration. It is often a sign of upper airway obstruction, such as in croup or anaphylaxis. Stridor results from turbulent airflow through a partially obstructed or narrowed larynx or trachea.

D. Crackles: Crackles, also known as rales, are brief, discontinuous, popping sounds heard on inspiration. They can be fine or coarse and are often associated with conditions that cause fluid or secretions in the alveoli or small airways, such as pneumonia or heart failure. Crackles are not typically associated with pleuritis.