This/that/that

For comparative tasting choosing between two first requires knowing they are different.

With two options, there is a 50/50 chance that you can guess one.

So we make it harder to guess: Three samples, two of them the same. Find the two that are the same, and then compare them against the odd one.

Whenever presented with a this/that question like this, wonder how can it be changed in this/that/that.