Correct option is C
Asthma is a condition characterized by airway inflammation and bronchoconstriction, leading to narrowed airways. This produces wheezing—a high-pitched, musical sound heard mostly during expiration. It is one of the hallmark signs of an asthma exacerbation and is critical for diagnosis and monitoring severity.
Explanation of options: (a) ✘ Murmurs – Heart sounds related to turbulent blood flow, not respiratory in origin. (b) ✘ Korotkoff sounds – Heard during blood pressure measurement, not related to lung pathology. (c) ✔ Wheezing – High-pitched sound due to narrowed airways in asthma. (d) ✘ Pleural friction rub – Associated with pleuritis, not typically seen in asthma.