The item that should be removed from the poster of non-verbal cues used in active listening is "maintain a neutral expression."
In active listening, having an engaged and responsive facial expression is important, rather than maintaining a neutral expression, which may signal disinterest or lack of engagement. The other items—nodding in acknowledgment, aligning your body with the speaker's body, and looking the speaker in the eye—are all effective non-verbal cues that indicate active listening.