The answer for this question would be B. Both elements, one being a Group 1 and the other being a Group 17, want to attain the octet of electrons in the outermost shell for chemical stability. The Group 1 element has one too many electrons, and the 17 is lacking one. To increase the stability of the system, the Group 1 can donate the extra electron to the Group 17 so that both can emulate a stable octet. In doing so, two ions are produced (elements that have a net charge that isn’t 0), and thus we have an “ionic bond.”
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