Can someone help me with this, i don’t really understand it

1. what are the missing reasons in the proof 2. it's in the second picture and 3

If the slope of one line equals the slope of another line then ? a) the two lines are intersecting lines b) the two lines are perpendicular lines c) the two lines are parallel lines d) the two lines always have very steep slopes

Is it true or false i’m trying to pass this test so i can leave school