Group polarization is when inside a group what first was an inclination to some ideas, after the individuals talk, those same ideas become much more stronger and radical. As the exercise exemplifies, the jury is deliberating and their initial attitudes are leaning neutral to slighty toward a guilty verdict. After a few days of deliberation, their ideas have strengthened considerably toward a guilty verdict. That's a good example of group polarization.
From the options provided, the US presidency is the one who receives the most news coverage from the national press, above the other institutions mentioned.
