Final answer:
Sarah's refusal to hold hands with anyone, even those she is close to, is an example of an emotional boundary.
Step-by-step explanation:
This is an example of an emotional boundary. Boundaries refer to the limits and expectations that individuals set for themselves in order to protect their emotional, physical, and mental well-being. Sarah's preference of not holding hands with anyone, even those she is close to, indicates that she has set a personal boundary regarding physical touch.
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