The No. of odd degree vertices in any graph is always even.

In any graph sum of degrees of vertices is twice the no of edges.

So, Both are True.

In any graph sum of degrees of vertices is twice the no of edges.

So, Both are True.

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Both are correct

P: sum of odd degree $+$ sum of even degree$=2\times \text{no. of edges}$

sum of odd degree$=2\times \text{no. of edges - sum of even degree}$

The right hand side must be even as the difference of $2$ even numbers is always even.

Q: each edge is counted twice so sum of degree is always even

P: sum of odd degree $+$ sum of even degree$=2\times \text{no. of edges}$

sum of odd degree$=2\times \text{no. of edges - sum of even degree}$

The right hand side must be even as the difference of $2$ even numbers is always even.

Q: each edge is counted twice so sum of degree is always even