If this is true, which one of these sentences must also be true?

“Whoever stole the money must have had both an opportunity and a motive.”

If this is true, which one of these sentences must also be true?

If Finn had both an opportunity and a motive, he must have stolen the money. If Finn did not steal the money, he cannot have had an opportunity. If Finn did not steal the money, he cannot have had a motive. If Finn did not have a motive, he cannot have stolen the money.

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If this is true, which one of these sentences must also be true?