A real-world example of a plane from the given options is Option #3: a countertop.
In geometry, a plane is defined as a flat, two-dimensional surface that extends infinitely in all directions. A countertop represents a flat surface that can be considered a finite example of a plane.
Options #1 and #2 do not represent flat surfaces in the same way. A location on a map is a point rather than a surface, and a room has three dimensions.