Describe how tone of voice and facial expressions play a role in the delivery of

Describe how tone of voice and facial expressions play a role in the delivery of the polling questions.

A) In order to avoid discouraging one response over another and the skewing of results, pollsters must utilize sympathetic looks.
B) In order to avoid encouraging one response over another and the skewing of results, pollsters must avoid dressing to conservatively and sympathetic looks.
C) In order to avoid encouraging one response over another and the skewing of results, pollsters must avoid certain tones of voice and using foreign accents.
D) In order to avoid encouraging one response over another and the skewing of results, pollsters must avoid certain tones of voice and sympathetic looks.

This is for my political science class.