Which one of the following is the common factor of (4743 + 4343) and (4747 + 4347) ?

When n is odd, (xⁿ + aⁿ) is always divisible by (x + a).

Each one of (47⁴³ + 43⁴³) and (47⁴⁷ + 43⁴⁷) is divisible by (47 + 43).