The figure below shows a line graph and two shaded triangles that are similar: A line is shown on a coordinate grid. The x axis values are from negative 15 to positive 15 in increments of 3 for each grid line. The y axis values are from negative 5 to positive 5 in increments of 1 for each grid line. The line passes through the ordered pairs negative 12, 4, and 0, 0, and 12, negative 4. A shaded right triangle is formed so that its hypotenuse is from ordered pair 0, 0 labeled as O to 6, negative 2 labeled as A, one leg is from 0, 0 to 0, negative 2, and the second leg is from 0, negative 2 to 6, negative 2. Another shaded right triangle is formed with the hypotenuse from 6, negative 2 to 9, negative 3 labeled as B, one leg is from 6, negative 2 to 6, negative 3, and the second leg is from 6, negative 3 to 9, negative 3.

Which statement about the slope of the line is true?

It is fraction negative 1 over 3 throughout the line.
It is −3 throughout the line.
The slope from point O to point A is fraction 1 over 3 times the slope of the line from point A to point B.
The slope from point O to point A is 3 times the slope of the line from point A to point B.