CEMC Fermat, 2011

Number theory Difficulty 2.0 Junior Find the answer Canada

If $m$ and $n$ are consecutive positive integers and $n^2 - m^2 > 20$ , then the minimum possible value of $n^2 + m^2$ is

(A) $29$ (B) $181$ (C) $265$ (D) $23$ (E) $221$

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