Answer:
The type of body movement in placing an index finger on lips to request silence is that of an emblem.
Explanation:
- The action of trying to convey to stop another action in progress can be referred to as an 'emblem'.
- When an action is controlled by posing a counter-action that has a conventionally accepted meaning, the action that is performed to 'control' can be called as the 'emblem' action owing to the meaning pre-assigned to it.