Let's try all of the possible answer choices.
Any result that is even, we cross off the list. Otherwise we have our answer.
If c = -8, then c-8 = -8-8 = -16 which is even. Cross this off the list
If c = 0, then c-8 = 0-8 = -8, which is even. Cross this off the list.
If c = -5, then c-8 = -5-8 = -13, which is odd. We have our answer
If c = 10, then c-8 = 10-8 = 2, which is even. Cross this off the list
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Final Answer: Choice C) -5
