An ideal fluid is flowing in a non-uniform cross-sectional tube XY (as shown in the figure) from end X to end Y. If $K_1$ and $K_2$ are the kinetic energy per unit volume of the fluid at X and Y respectively, then the correct option is: [add image]
A $K_1=K_2$
B $2K_1=K_2$
C $K_1>K_2$
D $K_1<K_2$