Which of these equations is not parabolic?

• A. \(\rho\dot{q}\frac{\partial}{\partial x}(k\frac{\partial T}{\partial x})+\frac{\partial}{\partial y}(k\frac{\partial T}{\partial y})+\frac{\partial}{\partial z}(k\frac{\partial T}{\partial z})=\rho\frac{\partial e}{\partial t}\)
• B. \(\rho\dot{q}+\frac{\partial}{\partial x}(k\frac{\partial T}{\partial x})=\rho\frac{\partial e}{\partial t}\)
• C. \(\frac{1}{\rho C_v}[\frac{\partial}{\partial x}(k\frac{\partial T}{\partial x})+\frac{\partial}{\partial y}(k \frac{\partial T}{\partial y})+\frac{\partial}{\partial z}(k\frac{\partial T}{\partial z})]=\frac{\partial T}{\partial t} \)
• D. \(\frac{\partial}{\partial x}(k\frac{\partial T}{\partial x})+\frac{\partial}{\partial y}(k \frac{\partial T}{\partial y})+\frac{\partial}{\partial z}(k\frac{\partial T}{\partial z})=0\)