Coplanar points are points that lie in same plane. If 4 points are in same line they are collinear and then they will be coplanar. If the 4 given points lie in same plane then also they will be coplanar. If they do not lie in same plane they will not be coplanar. The points can lie on different lines. Four or more points might or might not be coplanar.
<span>D. lie in the same plane. </span><span> The definition of capillarity is that points are considered as co-planar when these points are on the same plane, so it is obvious that the answer D is true because this statement is the definition of capillarity. This is shown in Figure 1.
</span><span>A. lie on the same line. </span><span> If four points lie on the same line then there will be a plane that contains this line, therefore the definition is fulfilled. This is shown in Figure 2.
</span><em>Finally, the correct answers are A. and D.</em>