if deg(a)=0 in a graph, is "a" counted as an even vertex or not?

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i was solving this test, and the answer of title affects the answer, so i was confused.

Q) in a simple graph, p=10 and 2q/p=3. the graph has 3 isolated vertices and all other vertices have a degree of 5 or 4, how many even vertices does this graph have?

1. (5) 2. (6) 3. (7) 4. (8)

thank you in advance (: