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Q4: Indicate which of the following five graphs 6 = (V, E), is not connected. A. G ={1,2} {1,2} {2,3} {3,4} {1,5} {1,5} B. G ={4,5} {1,3} {1,3} {2, 3} {2,5} {4, 5} C. G ={6,7} {1,3} {1,3} {2,3} {2,6} {6,7} D. G ={4,2} {2,5} {2,4} {4,5} {2,5} {6,7} E. G ={0,6} {6, 1} {6, 5} {2, 6} {1, 2} {4, 5} {3, 2}