Continuity equation for a compressible fluid is

A

$$A_1V_1 = A_2V_2$$

B

$$\rho_1A_1V_1 = \rho_2A_2V_2 (A \rightarrow area)$$

C

$$\frac{A_1V_1}{\rho_1} = \frac{A_2V_2}{\rho_2} (V \rightarrow velocity)$$

D

$$\frac{\rho_1A_1}{V_1} = \frac{\rho_2A_2}{V_2} (\rho \rightarrow density)$$