Angles between South and West and South and East are
making a linear pair
Understand that linear pairs of angles are those pairs of angles that are constructed by a common pair of rays or line segments.
Refer to figure.
Angle between South and West is and between South and East is . The sum is
It is clear from the figure that the angles between South and West and South and East are linear pairs of angles.
Hence, the correct option is (c) i.e. making a linear pair.