In the Quadratic Regression Model $\mathrm { y } = \beta _ { 0 } + \beta _ { 1 } X _ { 1 } + \beta _ { 2 } X _ { 1 } ^ { 2 } + \varepsilon \text {, }$

Multiple Choice

In the quadratic regression model $\mathrm { y } = \beta _ { 0 } + \beta _ { 1 } X _ { 1 } + \beta _ { 2 } X _ { 1 } ^ { 2 } + \varepsilon \text {, }$
The ?₁ term represents the:

A) Rate of curvature of the parabolA.
B) Value of Y when X is zero.
C) Shift parameter of the parabola.
D) Y-intercept of the parabola.