I'm the other way around, Classica. To me, "then you've got another think coming" makes no sense. It's not really a valid/grammatical usage of the verb.

OTOH, the following makes perfect sense to me:

"Well, if [Thing A] is what you think/expect, then you've got another thing coming."

Of course, looking back, now that it's been explained to me that it's a cute little play on "think" that's not really supposed to make complete sense, I can sort of get "another think coming," but "thing" is still how I've always heard it and what makes sense to me.

*shrug*

Incidentally...

Quote
Which of the following sentences are correct?
Is incorrect. Which is singular. Think of it like this: "Which [one] of the following..."

Therefore, it should be "Which ... is correct?"

Paul

When in doubt, think about penguins. It probably won't help, but at least it'll be fun.