I'm preparing for an entrance exam and got stuck on a question.

Let $f(x)$ be a polynomial of degree greater than $1$. If $f(x)$ is divided by $x-a$, then $f(a)$ is the remainder.

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> Q1) Let $f(x) = x^{2013} +1$, then remainder when $f(x)$ is divided by $x^2 -1$ is:
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> A) $x-1$
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> B) $x+1$
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> C) $0$
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> D) $1$
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