Final answer:
The optimal way for a nursing assistant to inquire about a resident not eating breakfast is to ask about their well-being, thus fostering an open conversation about the individual's feelings and potential reasons for the lack of appetite.
Step-by-step explanation:
To best obtain information about why a resident did not eat his or her breakfast, the nursing assistant should adopt a strategy that opens up a dialogue and encourages the resident to talk about their feelings and potential reasons for not eating. Among the options provided, asking “How are you feeling today?” is the most effective approach as it addresses the person's well-being and could lead to understanding underlying issues such as loss of appetite due to emotional distress or physical discomfort. Observation and communication are crucial in healthcare settings to ensure that the needs of residents are met and their health is monitored effectively.