Select the option that can be used as a one-word substitute for the given group of words.
Formally put an end to a system, practice, or institution

The correct answer is Abolish.

Step-by-step Explanation:
1. Analyze the given group of words: The phrase is "Formally put an end to a system, practice, or institution".
2. Examine the options provided:
- Stop: This means to come to an end or cease from action. While it means to end something, it is a general term and does not carry the connotation of "formal" or "institutional" ending.
- Destroy: This means to end the existence of something by damaging or attacking it. This is usually physical and not a formal legal or institutional process.
- Kill: This means to cause the death of a person, animal, or other living thing, or to put an end to something completely (often abruptly). It is not a formal vocabulary term for ending a system or practice.
- Abolish: This specifically means to formally and officially put an end to a law, system, practice, or institution (for example, "to abolish slavery" or "to abolish a tax").
3. Conclusion: Therefore, the word that best fits as a one-word substitute for formally ending a system or practice is Abolish.