Final answer:
The development of legislative oversight is an example of an informal practice in the U.S. federal system of government.
Step-by-step explanation:
An example of an informal practice that emerged in the U.S. federal system of government is the development of legislative oversight. Legislative oversight refers to the monitoring and supervision of the executive branch by the legislative branch, ensuring that laws are implemented properly and government actions are in line with legislative intent. It is an informal practice because it is not explicitly mentioned in the U.S. Constitution but has become an integral part of the legislative process.
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