A nurse is assessing a client who has asthma and signs of cyanosis. Which of the following is a reliable indicator of cyanosis?

A. Tip of the nose: The nose can show cyanosis in severe cases but is less reliable because peripheral vasoconstriction and temperature can affect its appearance. B. Ear lobes: Earlobes may reflect peripheral circulation but are not the most consistent site for detecting cyanosis. C. Forearms: The forearms are usually not reliable for detecting cyanosis because skin coloration and perfusion vary. D. Nail beds: Nail beds (or mucous membranes when available) provide a reliable and commonly used site to detect cyanosis due to their visibility of capillary oxygenation.