73%
Help the confused homeowner deduce what is inside a mystery package left on the porch.
"This box is as light as a feather! It _________________________ be the heavy bowling ball I ordered.
Wait, it's shaped exactly like a guitar case, so it _________________________ be that vintage acoustic guitar you won at the auction!
Let me check the label... the address is slightly smudged. It _________________________ belong to our neighbor, Mr. Henderson, but I'm not entirely sure."
can't
A light box cannot possibly contain a heavy bowling ball, so we use can't for a strong negative deduction.
must
The distinct shape of a guitar case provides strong evidence, so we use must for a confident positive deduction.
might
The smudged label leaves room for doubt. The speaker explicitly says "I'm not entirely sure," making might the perfect choice for a possibility.