On which Big Five trait would such people score highest?

Neuroticism reflects emotional instability and a tendency towards anxiety and moodiness. Individuals scoring high in this trait often struggle with negative emotions and may exhibit a lack of self-control, which contrasts with the responsible and organized nature of those high in Conscientiousness.

Extraversion is associated with sociability, assertiveness, and high energy levels. While extraverts thrive in social situations and are often enthusiastic, they may not necessarily exhibit the meticulousness or reliability characterizing high Conscientiousness scores.

Agreeableness encompasses traits such as kindness, empathy, and cooperativeness. Although agreeable individuals are often well-liked and harmonious, this trait does not directly correlate with the responsibility and organization inherent to Conscientiousness.

Openness involves creativity, curiosity, and a willingness to consider new ideas. While open individuals may be innovative and imaginative, this trait is not synonymous with the disciplined and responsible nature associated with high Conscientiousness.