Recall that the equation of a horizontal line has the form:
[tex]\begin{gathered} y=k, \\ \text{where k constant is a real number.} \end{gathered}[/tex]Since the given equation is:
[tex]y=0,[/tex]then it is the equation of a horizontal line.
Now, the lines parallel to a horizontal line must be horizontal lines too, therefore, the equation that represents a line that is parallel to y=0 is:
[tex]y=-7.[/tex]Answer: Option C.
