Hi Ryn, For cannot be true options in logic games we have a few possible approaches. First, we can rule out any options that we know could be true based on previous game boards. Generally, then, we look through the remaining options to see if we can tell if anything cannot be true based on the rules. If we aren't able to come up with any deductions as to which one would not be true, then yes we can try out the answer choices. Usually testing the answer choices one-by-one should be a last resort approach because it can take a lot of time, but for hard questions we may have to do this. Hope this helps!
