#### Answer

The degree of vertex A, vertex C, and vertex D is 3. Vertex B has a degree of 5. Therefore, each vertex is an odd vertex.
Since each vertex is odd, this is a graph with four odd vertices and one loop at vertex B.

#### Work Step by Step

The degree of a vertex is the number of edges connected to the vertex. If the degree of a vertex is an odd number, then the vertex is an odd vertex.
We can draw a graph with four vertices with edges AB, AC, AD, BD, CD, and BC. Then the degree of vertex A, vertex C, and vertex D is 3. Vertex B has a loop and a loop adds 2 to the degree of the vertex. Vertex B has a degree of 5. Therefore, each vertex is an odd vertex.
Since each vertex is odd, this is a graph with four odd vertices and one loop at vertex B.