Final answer:
The subjective data in the patient's complaint is D. Chest tightness, as it is information reported by the patient that cannot be directly measured or observed by the healthcare provider.
Step-by-step explanation:
In the assessment of a new patient who is experiencing chest tightness, a temperature of 100F, an oxygen saturation of 89%, and is expelling frothy mucus, the example of subjective data is D. Chest tightness. Subjective data refers to information that is reported by the patient and cannot be directly measured or observed by the healthcare provider, such as feelings of tightness in the chest, pain, or nausea. On the other hand, objective data include the temperature, oxygen saturation, and the appearance of the mucus, which are measurable or observable signs of the patient's condition. This kind of data can be quantified or confirmed through diagnostic tests and physical exams, for example, using a thermometer for temperature, a pulse oximeter for oxygen saturation, and visual or microscopic examination of the sputum.