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The correct answer to question "c" is one component.
In graph theory, a component, sometimes called a connected component, of an undirected graph is a subgraph in which
any two vertices are connected to each other by paths, and which is connected to no additional vertices in the supergraph.
A graph that is itself connected has exactly one component, consisting of the whole graph.
See this Wikipedia article
https://en.wikipedia.org/wiki/Component_(graph_theory)#:~:text=In%20graph%20theory%2C%20a%20component,additional%20vertices%20in%20the%20supergraph.&text=A%20vertex%20with%20no%20incident%20edges%20is%20itself%20a%20component.