This is the difference between a veteran teacher and someone not from the teaching community( like me!
). The way you asked the question with diagrams leaves no iota of doubt in what is being sought!
All the three cases with diagrams that you have cited are examples of Standalone S/D zones. Let me take this opportunity to explain "Standalone S/D zones".
A Standalone zone is one that is not formed by virtue of reacting from another S/D zone. This diagram should explain the concept:
In this case, Zone 3 is a Standalone DZ since it formed on its own without the help of any other DZ, whreas DZ 2 formed after reacting from DZ 1 so DZ 2 is not a Standalone zone.
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More examples:
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