What does it mean to be 'nonplused'?

To be 'nonplused' means to be filled with bewilderment or confusion. The term originates from a Latin phrase meaning "not more," suggesting a state of being at a loss for words or unsure of how to proceed. When someone is nonplused, they may feel perplexed and uncertain about a situation, often as a result of unexpected events or surprising information that leaves them momentarily speechless or unsure of how to react. In contrast, the other choices—filled with excitement, concern, or joy—represent positive or feeling-driven states that do not align with the sense of confusion implied by being nonplused. Thus, the correct answer highlights the essence of being overwhelmed by bewilderment, rather than a specific emotional response.