Which graph shows a line with a slope of zero?
A coordinate grid with x and y axes ranging from negative seven to seven in increments of one is shown. A vertical line is drawn passing through three, zero.
A coordinate grid with x and y axes ranging from negative seven to seven in increments of one is shown. A horizontal line is drawn passing through zero, two.
A coordinate grid with x and y axes ranging from negative seven to seven in increments of one is shown. A line is drawn passing through three, four and negative six, negative five.
A coordinate grid with x and y axes ranging from negative seven to seven in increments of one is shown. A line is drawn passing through zero, one and one, zero.