A tree has 10 vertices. How many edges does it contain?

Options

  • A. 9
  • B. 10
  • C. 11
  • D. More than one of the above
  • E. None of the above

Correct Answer (Detailed Explanation is Below)

A. 9

Detailed Explanation

Every tree containing N vertices has N - 1 edges. Therefore, a tree with 10 vertices contains 10 - 1 = 9 edges. A tree is a connected acyclic graph. Removing any edge from a tree disconnects it, while adding an edge between two existing vertices creates exactly one cycle. Remember the important relationship: vertices = N, edges = N - 1.