Final answer:
Disapproval is an example of an informal sanction, while fines, imprisonment, and probation are examples of formal sanctions.
Step-by-step explanation:
An example of an informal sanction is disapproval. Informal sanctions are typically seen in face-to-face social interactions. For instance, if you wear flip-flops to an opera or swear loudly in church, you may receive disapproving looks or even verbal reprimands as informal sanctions. On the other hand, fines, imprisonment, and probation are examples of formal sanctions which are ways to officially recognize and enforce norm violations.