Which subjective assessment data supports the nurse's conclusion that a client is experiencing orthopnea?

A. "I cough a lot at night and it keeps me up half the night." Night-time coughing can be associated with various conditions, including asthma, GERD, or postnasal drip, but it is not specifically indicative of orthopnoea. B. "I sleep on three pillows at night." This supports orthopnoea, which is difficulty breathing when lying flat. Clients with orthopnoea often use multiple pillows to elevate their upper body to alleviate shortness of breath. C. "I have multiple attacks of wheezing almost daily." Frequent wheezing is more indicative of asthma or other obstructive airway diseases, not orthopnoea. D. "It doesn't take much activity before I'm out of breath." This describes dyspnoea on exertion, which is different from orthopnoea, as it refers to difficulty breathing during physical activity rather than when lying down.