What's wrong with this proof that an even number plus an even number is even? Suppose n and m are even numbers. Then n is 2k and m is 2k as well. It follows that their sum is 2k plus 2k. By using the laws of algebra, we can show that 2k plus 2k is 4k, or 2 times 2k. Hence, n plus m is even by definition of even number. Group of answer choices Variable name literalism: while an even number can always be written as 2k for some integer k, two potentially different even numbers will not be equal to 2k for the same k. A correct proof must use two different variable names like this: Then n = 2p and m = 2q for some integers p, q. The proof is much too verbose. A good proof is concise. We don't usually spell out standard arithmetic operators in English: we usually write instead of "plus". We also don't spell out obvious things like the fact that we are using the laws of algebra when we're doing algebra. The quantification "for some integer k" is missing from "n = 2k". Without the quantification, the statement "n = 2k