The slope of the line that passes through (-9, -6) and (3, -9) is -1/4, the correct option is C.
How to find the slope?
If a line passes through two points (x₁, y₁) and (x₂, y₂), then the slope is given by the formula:
a = (y₂ - y₁)/(x₂ - x₁)
Here we have the points (-9, -6) and (3, -9), replacing that in the slope formula we will get:
a = (-9 + 6)/(3 + 9)
a = -3/12
a = -1/4
The correct option is C.