Which of the equations below represents a line parallel to the x-axis

y = (constant not 0)

Step-by-step explanation:

"Which of the equations below"? What are those?

The general form for an equation parallel to the x-axis is y = ... ( ... being a real number) because the y-value would remain constant, similar to how the x-axis is constantly at y=0. (Not 0, because parallel lines technically never intersect.)