\textbf{149-} The degrees of the vertices of a simple and connected graph with vertices $4, 3, 1, a, b, c$ are given. If $p$ is the number of vertices of the graph, $q$ is the number of edges of the graph, and $q = \dfrac{3}{2}p$, then the number of elements of the set $\{a, b, c\}$ is which of the following?
$$1 \ (1) \hspace{2cm} 2 \ (2) \hspace{2cm} 3 \ (3) \hspace{2cm} 4 \ (4)$$
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