Continuity equation can take the form
(where A = Area, V = Volume, ρ = Density and P = Pressure)

Correct option is C

The continuity equation in fluid dynamics expresses the conservation of mass in a flowing fluid. For an compressible fluid (where density can vary ), the mass flow rate must remain the same from one cross-section to another. This can be represented by the equation: $$\rho_1 A_1 V_1 = \rho_2 A_2 V_2$$​​

For an incompressible fluid, the density (ρ)cancels out, simplifying the equation to:
$$A_1V_1 = A_2V_2$$​
This form of the equation relates the product of area and velocity (volume flow rate) at two different cross-sections of a pipe or duct.