Any county may have the right to elect three (3) road commissioners from the county at large, who shall be the road commissioners for the county, and who shall have the supervision of the construction of the roads in the county; provided, that any county that does not desire to elect its road commissioners from the county at large may subdivide its county into road districts as is provided for in § 54-9-115; and provided, further, that, in any county electing its road commissioners from the county at large, no two (2) of the road commissioners shall be from the same civil district.