'Ordered Arrangement' basically means that it is a solid at room temperature. Room temperature is approximately 15-20C so we are looking for melting and boiling points that are above room temperature so it hasn't/can't melt or boil at room temperature and would therefore be solid. Option C is the only one where both points are temperatures above room temperature therefore option C is the only one where the substance would be in an 'ordered arrangement' at room temperature.
