Which of the following is true about Handshaking Lemma?

Select one:

a. In Handshaking lemma, If the degree of a vertex is even, the vertex is called an even vertex

a. In Handshaking lemma, If the degree of a vertex is even, the vertex is called an even vertex

b. The sum of all the degrees of all the vertices is equal to twice the number of edges.

b. The sum of all the degrees of all the vertices is equal to twice the number of edges.

c. The degree of a vertex is odd, the vertex is called an odd vertex.

c. The degree of a vertex is odd, the vertex is called an odd vertex.

d. The degree of a graph is the largest vertex degree of that graph.