Select the CORRECT option that shows the match between Geometry and Error Type in vector data digitization.
Geometry (P) Tiny graphic polygons (Q) Open polygons (R) Overshoot/undershoot (S) Polygons with inadmissible loops
Error Type (1) Sliver polygon (2) Dangle (3) Weird polygon
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Separate the errors into two families: ones caused by a duplicated/misaligned boundary line (sliver polygons) and ones caused by an unconnected line end (dangles); a self-crossing boundary is a weird polygon.
Step 1: Group the four geometry errors by their root cause. Digitizing errors in a vector layer generally fall into two families: those caused by a duplicated or misaligned boundary line, and those caused by a line that fails to properly connect to another line or to itself. Sorting P, Q, R, S into these two families first makes the matching much easier.
Step 2: Duplicated/misaligned boundary family (sliver polygons). When the same physical boundary is captured twice with a small positional mismatch, the thin strip of area enclosed between the two near-duplicate lines is a sliver polygon. This is visually a tiny graphic polygon, so (P) Tiny graphic polygons matches (1) Sliver polygon.
Step 3: Unconnected-end family (dangles). A dangle is a node with only one line attached. This happens in two situations here: first, (R) Overshoot/undershoot, where a line is digitized either too far past, or not far enough to reach, the node it should connect to, leaving a free end; second, (Q) Open polygons, where the polygon's boundary is not snapped into a closed loop, so the last digitized point never connects back to the first, again leaving a free end. Both (Q) and (R) therefore match (2) Dangle.
Step 4: Self-crossing family (weird polygons). (S) Polygons with inadmissible loops means the boundary line crosses itself somewhere along its path, producing a self-intersecting, bowtie-like shape instead of a simple non-crossing loop. Such an abnormal shape is called a weird polygon, so (S) matches (3) Weird polygon.
Step 5: Final match and check against choices. Combining all four pairs gives P-1, Q-2, R-2, S-3. Checking the four given options, only the first option lists exactly this combination, the others misassign either P or Q to the wrong error type.
