What graph passes the vertical line test?

The fourth image, or D.

Why?

If you had a ruler and placed it on the grid vertically and moved the ruler left to right, pictures A, B, and C, all have two points that lay on the same X point.

Picture D is the only one that has no points that lay on the same X point, thus making it the right answer.

Thank you for reading into this.

(Hope this helps you! ^^)

the slope of the first function is -3. (3/1)

the slope of the second function is 1. (13-10/6-3).

since |-3| is greater than |1|, the function with the steepest slope is the first.