Water falls from a tap, down the streamline

Explanation

The correct answer is that the area decreases. As the water falls from the tap, it accelerates under gravity, increasing its velocity. According to the principle of continuity, which states that the product of cross-sectional area and velocity remains constant for an incompressible fluid, the cross-sectional area of the stream must decrease as velocity increases. This is why the stream of water narrows as it falls. The other options are incorrect because they do not account for the effect of gravity on the falling water and the principles governing fluid flow.