Explanation:

- Theft: This is when someone takes someone else's property without their consent, with the intent to permanently deprive them of it. It doesn’t involve fear or force.

- Robbery: This involves taking property from someone’s possession through force or fear. It’s a violent crime and involves personal confrontation.

- Dacoity: This is a term used in some legal systems to describe robbery when five or more people are involved. It's a collective robbery with violence.

- Extortion: This is obtaining property or money through coercion, such as threats of harm or revelation of secrets, not limited to immediate physical violence.

- In the scenario, A threatens B’s child to get B's purse. This is taking property by force or threat, classifying it as robbery.

- Correct Answer:

- Option: 2, Robbery.

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