An inciting incident is one that highlights/starts the main conflict. Of course, like many things, it's up for interpretation.
I think that in the case of Misery, it's when Annie "rescues" Paul from his accident. The accident itself is just an event. It could have been resolved if someone else finds him. But the action of Annie taking Paul in sets the whole thing in motion. But one can argue that Annie has been stalking Paul, and that's why she's on hand when the accident happens. So the accident could be the inciting incident...
As for (B), it's called a turning point.
For me, in Jaws, the inciting incident is when the Sherrif discovers the victim's hand. The shark attack is only an event. It can easily been unreported, etc. It's only when the sherrif finds the victim that sets the whole thing in motion (the main conflict: "shark attack" vs. "opening the beach for the season") So the shark attack is only a prologue. The story starts when the sherrif finds the hand.