The answer correct is C.
We can use the linear equation y=mx+b to help. y is the dependent variable, m is slope, x is the independent variable, and b is the y intercept.
In this case, the values of x and y were not given, so we still have y=mx+b. We can substitute 9/4 for m and -14 for b to get y=9/4x-15, which is C.