Which is the correct label of the parallel lines? parallel lines a and b are shown. points a and b lie on line a while points c and d lie on line b. the letters a and b are separated by two vertical lines. there is a horizontal line with arrows on either end over the letters a a. there is another horizontal line with arrows on either end over the letters c b. a vertical line with a horizontal line intersecting it at the bottom separates the two pairs. there is a horizontal line over the letter a with one arrow on the right end. there is a horizontal line over the letter b with one arrow on the right end. the letters are separated by two vertical lines. there is a horizontal line with arrows on either end over the letters a a. there is another horizontal line with arrows on either end over the letters c b. a vertical line with a horizontal line intersecting it at the bottom separates the two pairs.