A line that is parallel to the x-axis has a constant y-value for all x-values. The equation for such a line can be expressed as \( y = k \), where \( k \) is a constant.
From the options given:
A: \( x = 7y \) (not parallel to the x-axis)
B: \( y = 7 \) (parallel to the x-axis)
C: \( x = 7 \) (not parallel to the x-axis)
D: \( y = 7x \) (not parallel to the x-axis)
The correct choice is B: \( y = 7 \).