Objective data in healthcare refers to information that is:

Objective data in healthcare is primarily defined as information that is measurable and observable. This can include any data that can be recorded through direct observation or physical examination, such as vital signs, lab results, imaging studies, and other diagnostic tests. The characteristics of objective data are that it is factual and devoid of personal interpretation or bias.

The choice indicating that objective data refers to what is "heard, felt, or smelled" aligns with this definition because it encompasses the types of observations a healthcare professional can make through their senses. For instance, a healthcare provider might note abnormal lung sounds (heard), tenderness in an area (felt), or unusual odors (smelled) that could indicate a medical issue.

The other options do not accurately reflect the concept of objective data. Claims that it is "subjective and opinion-based" or "based on personal feelings" contradict the very nature of objectivity, which requires detachment from personal bias. Likewise, stating that it is "only what is reported by the patient" fails to recognize that objective data is generated from direct observations and measurements rather than solely relying on patient self-reports.