Dr Hewitt is able to break the piece of wood in his demonstration given that he had knowledge about the concept of momentum, which is esentially the product of the mass and speed of an object.
Aplying this idea, he used the correct momentum of his hand over a short period of time and that is how he was able to break the piece of wood.
The way in which our actions are initiated, sustained, and directed is called motivation. Motivation refers to the dynamics of our behaviors. Hope this helped!
I say it is probably b because law is a list of rules to go by ladder don’t really know but pretty sure it doesn’t mean that I’m assuming it is b because we learned that a long time ago but don’t know if it the same meaning for you