A Linear Regression Equation of the Form Y = a $\Delta$

Multiple Choice

a linear regression equation of the form Y = a + bX,the slope parameter b shows

A) $\Delta$ X / $\Delta$ Y.
B) $\Delta$ Y / $\Delta$ X.
C) $\Delta$ Y / $\Delta$ b.
D) $\Delta$ X / $\Delta$ b.
E) none of the above