B. Natural selection
Natural selection is the most important force of evolution. Other forces of evolution are mutation, gene flow and genetic drift.
The answer is
Postural Tremor. Kinetic tremors occur during movement of a body part, such as
moving your wrist up and down. Task-specific tremors occur during a particular
activity, such as writing. A postural tremor transpires when holding a position
against gravity, such as holding your arm or leg outspread.
