Which of the following graph is/are planer? Choose the most appropriate answer…
2025
Which of the following graph is/are planer?
Choose the most appropriate answer from the options given below:
- A.
A and C only
- B.
B only
- C.
A only
- D.
A and B only
Attempted by 156 students.
Show answer & explanation
Correct answer: D
A graph is planar if it can be drawn on a plane without any edges crossing. We analyze each graph:
Graph (A): This graph is planar because the given drawing has no edge crossings. It is already in a planar embedding.
Graph (B): This graph appears to have edge crossings, but it is planar because the vertices can be rearranged to eliminate all crossings. Planarity depends on the existence of a crossing-free drawing, not the given one.
Graph (C): This graph is non-planar. It contains a subgraph that is homeomorphic to the utility graph (K3,3), which is a known non-planar graph. No matter how the vertices are arranged, at least one edge crossing will occur.
Therefore, only graphs A and B are planar.
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