What does the term 'ebullient' describe?

The term 'ebullient' is used to describe someone who is enthusiastic, energetic, and exuberant. It conveys a sense of joy and a high-spirited demeanor that is unrestrained and overflowing. When a person is described as ebullient, it suggests that they express their happiness or excitement openly and vivaciously, making C, "joyously unrestrained," the most accurate choice.

In contrast, the other options reflect a more subdued or restricted emotional state. For instance, describing someone as "joyously restrained" implies an acknowledgment of happiness but within limits, which contradicts the essence of ebullience. Similarly, "emotionally flat" suggests a lack of emotion or enthusiasm, and "calmly introspective" indicates a thoughtful and reflective state that is not characterized by being high-energy or exuberantly happy. Thus, the essence of the word 'ebullient' aligns precisely with the idea of being joyously unrestrained.