Free Practice Quiz Question List

09 Introduction to Graph Theory Online Quiz Questions

Use this free practice quiz with 20 questions to review 09 Introduction to Graph Theory, test your knowledge, and prepare for your next test or exam.

20 questions
01
True or false
1 point

For a simple undirected graph, the adjacency matrix is symmetric.

  1. A

    True

  2. B

    False

02
Written response
1 point

A simple undirected graph has edges xyxy, xzxz, and xwxw incident with vertex xx, and no other edge incident with xx. What is deg⁡(x)\deg(x)?

03
Fill in the blank
1 point

Complete each definition. A walk that does not repeat an edge is a . A walk that does not repeat a vertex is a .

04
Choose one
1 point

Let GG have vertex set V={a,b,c,d}V=\{a,b,c,d\} and edge set E={ab,bc,cd}E=\{ab,bc,cd\}. Which graph is a spanning subgraph of GG?

  1. A

    H=({a,b,c},{ab,bc})H=(\{a,b,c\},\{ab,bc\})

  2. B

    H=({a,b,c,d},{ab,bc,cd,da})H=(\{a,b,c,d\},\{ab,bc,cd,da\})

  3. C

    H=({a,b,c,d},{ab,bc})H=(\{a,b,c,d\},\{ab,bc\})

  4. D

    H=({a,b},{ab})H=(\{a,b\},\{ab\})

05
Choose all
1 point

Which statements correctly describe graph representations or their uses? Select all that apply.

  1. A

    An adjacency list is often memory-efficient for a sparse graph.

  2. B

    An adjacency matrix is always more memory-efficient than an adjacency list for a sparse graph.

  3. C

    An edge list directly records the graph's edges.

  4. D

    An adjacency list must contain a separate matrix row for every pair of vertices.

06
True or false
1 point

If a graph is connected, then there is exactly one path between every pair of vertices.

  1. A

    True

  2. B

    False

07
Written response
1 point

A graph has edges uvuv, vwvw, wzwz, and vzvz. What is the distance d(u,z)d(u,z), measured as the number of edges in a shortest path?

08
Fill in the blank
1 point

Complete each statement. A connected graph with no cycles is a . A vertex with degree zero is .

09
Choose one
1 point

A simple graph has edges abab, bcbc, cdcd, dada, and acac. Which sequence is a cycle?

  1. A

    a,b,c,a,da,b,c,a,d

  2. B

    a,b,c,d,aa,b,c,d,a

  3. C

    a,b,a,ca,b,a,c

  4. D

    a,c,b,da,c,b,d

10
True or false
1 point

In an undirected graph, a loop contributes 2 to the degree of its incident vertex.

  1. A

    True

  2. B

    False

11
Choose all
1 point

A graph has vertex set {a,b,c,d,e,f}\{a,b,c,d,e,f\} and edge set {ab,bc,de}\{ab,bc,de\}. Select all of its connected components, giving each component by its vertex set.

  1. A

    {a,b,c}\{a,b,c\}

  2. B

    {d,e}\{d,e\}

  3. C

    {f}\{f\}

  4. D

    {a,b,c,d,e,f}\{a,b,c,d,e,f\}

12
Open ended
1 point

Explain the difference between a spanning subgraph and an induced subgraph. Include what each must retain from the original graph and why a subgraph with the same selected vertices might fail to be induced.

13
Choose one
1 point

In an incidence matrix for a simple undirected graph, what does one column represent?

  1. A

    A column lists all neighbors of one vertex.

  2. B

    A column identifies the two endpoints of one edge.

  3. C

    A row gives the degree sequence of the graph.

  4. D

    A row records whether the graph is connected.

14
Choose one
1 point

A simple undirected graph is represented by an adjacency matrix. Which property must the matrix have?

  1. A

    Every entry on the diagonal must be 1.

  2. B

    The matrix must be symmetric.

  3. C

    Every row must contain the same number of 1s.

  4. D

    The matrix must have more 1s than 0s.

15
Choose one
1 point

For the graph V={a,b,c,d}V=\{a,b,c,d\} with E={ab,ac,bc,cd}E=\{ab,ac,bc,cd\}, which is the degree sequence when written in nonincreasing order?

  1. A

    (2,2,3,1)(2,2,3,1)

  2. B

    (4,2,1,1)(4,2,1,1)

  3. C

    (3,2,2,1)(3,2,2,1)

  4. D

    (3,3,1,1)(3,3,1,1)

16
Written response
1 point

A graph has vertex set {a,b,c,d,e}\{a,b,c,d,e\} and edges ab,bc,deab,bc,de. How many connected components does it have?

17
Choose one
1 point

In a graph containing the edges abab and bcbc, how should the vertex sequence a,b,c,ba,b,c,b be classified?

  1. A

    A path, trail, and walk

  2. B

    A walk but neither a trail nor a path

  3. C

    A trail but not a path or walk

  4. D

    Neither a walk, trail, nor path

18
Written response
1 point

Which graph representation is usually efficient for a sparse graph because it records only the neighbors that each vertex actually has?

19
Choose one
1 point

Let GG have V={a,b,c,d}V=\{a,b,c,d\} and E={ab,ac,bc,cd}E=\{ab,ac,bc,cd\}. Which edge set must the subgraph induced by W={a,b,c}W=\{a,b,c\} contain?

  1. A

    Only abab

  2. B

    abab and bcbc only

  3. C

    abab, acac, and bcbc

  4. D

    abab, acac, bcbc, and cdcd

20
Choose one
1 point

Which number of odd-degree vertices could a finite undirected graph have?

  1. A

    3

  2. B

    5

  3. C

    7

  4. D

    8