A sentence given with a blank is to be filled in with an appropriate word. Select the correct alternative out of the four.
"Either you're a mind reader or it's a ______________ that you called me just as I was keying your phone number."

* Coincidence means a remarkable concurrence of events or circumstances without apparent causal connection. Calling someone exactly when they are dialing your number is a classic example of a coincidence.
Correlation means a mutual relationship or connection between two or more things.

Union means the action of joining together.

Happening means an event or occurrence.