Angles that are opposite to each other when two lines cross are equal, therefore angle 1 is equal to angle 4. This also implies that angle 1 = angle 5. When a line crosses two parallel lines, the angles corresponding to each other are equal. So, if r and s are parallel, the angles that are formed when line l intersects line r are equal to those when l intersects line s. Thus, we have angle 1 = angle 5, angle 2 = angle 6, and so on. Hence, since angle 1 is equal to angle 5, we deduce that lines r and s are parallel.
It is option A. Step-by-step explanation: I just completed the task successfully.
