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No.. your answer is wrong. But That's good idea!

ah.. the answer is 5. in the first 2 diamonds, the outer numbers are divisible by 2. in the final diamond, if you were to switch one of the 3's with the question mark, then they would also have to be in some kind of numerical order. divisible by 2 doesn't work so the only option left is to put them in regular order (ie: 1,2,3,4 etc) leaving 5 the only answer